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Service

Invoicing software development

For owners and finance leads in trades, consultancies and small product businesses who need quotes with optional items and expiry, acceptance that is evidenced, invoices that follow deposits and stages, reminders that run themselves and a payment status that is always current, designed around how the business actually sells and gets paid.

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The problem

What goes wrong today

Where it usually starts

A kitchen fitting business with two installation teams quotes from a spreadsheet template.

  • Each quote is a copy of the last one with lines changed, so an optional extra the customer declined on the previous job occasionally survives into the next.
  • The customer accepts by text message, which has to be found again when the scope is disputed.
  • The deposit invoice is typed separately in a different template, with a number chosen by looking at the last one sent, and the balance invoice is typed again at the end, by which time two variations agreed on site have been forgotten.

Where it gets harder

Payments arrive by bank transfer with references that bear no relation to the invoice number, so the owner matches them from the bank statement on Sunday evenings.

  • Reminders go out when he remembers, which means the politest customers are chased and the slowest are not.
  • A supplier price rise changes the cost of every open quote but none of them is updated.
  • The accountant receives a folder of PDFs and a list of payments that do not reconcile, and the owner cannot say how much is quoted, how much is accepted and how much is outstanding without opening three files.

Scope of the service

What the build covers

A custom quotation and invoicing build normally covers the document trail from first quote to final payment. A quote builder composes line items from a price list you maintain, with optional items the client can tick, quantity and unit rules, versions when the scope changes and an expiry date after which the quote closes itself. Online acceptance presents the quote to the client, captures a signature and the options chosen, and records who accepted, when and which version. Conversion to invoice creates the deposit, stage and balance invoices from the accepted quote according to the payment schedule you set, each numbered from one sequence, with part payments recorded against the right invoice. Recurring invoices handle retainers and maintenance contracts. Payment links through a payment adapter let clients pay by card, while bank transfer reconciliation matches incoming amounts to invoices by reference, amount and date and flags the rest for a human. Credit notes correct invoices without altering a sent document. A reminder schedule chases overdue invoices on the cadence you decide, stopping as soon as payment lands. Branded PDF templates render quotes, invoices, credit notes and statements. A client portal shows each client their documents, their payment status and the acceptance history.

We work through the business with you first: how quotes are built and what is optional, how acceptance is evidenced, what the payment schedule looks like for a typical job, whether retainers exist, how payments arrive and get matched, what the reminder tone and cadence should be and what the accountant needs each month. Each becomes a named workflow stage in the scope document.

Deliberately out of scope

  • The ledger itself, which stays with your accounting platform and receives invoices, credit notes and payments through integration
  • Tax returns and submissions of any kind
  • Job scheduling or stock control, which have their own packages. The system records what was quoted, accepted, invoiced and paid
  • The tax treatment of each line is set by the business and checked by its accountant, and the figures remain their responsibility

When the scope grows

Scoping scenario

A fit-out contractor wants quotes assembled from a materials price list that updates from supplier files, variations added on site from a phone that create a signed supplementary quote, stage invoices triggered by stage completion in a separate job system, and retention amounts held back and invoiced on a later date. Supplier-fed pricing, site variations and retention invoicing make this a custom build, and the scope document says so plainly.

Deliverables

What you receive

  • Discovery notes from following a real job from quote to final payment through your business
  • A written scope document naming each stage from quote to reconciliation, the payment schedule rules, the reminder cadence and what is left out
  • Designs of the quote builder, the client acceptance screen, the invoice and payment view and the reminder settings on phone and desktop
  • The build, deployed to your hosting or ours, with your price list, templates and numbering configured
  • Migration of clients, open quotes, unpaid invoices and the numbering sequence from your current files or app
  • Training for the owner and whoever raises invoices, and a short guide for clients using the portal
  • Handover material and full ownership of the source code and your data

Process

How a project runs

Each stage maps onto the project view in your client panel. Durations are set in your proposal, never on this page.

  1. Onboarding

    Access to your current quote and invoice templates, price list, a sample of recent documents, your bank statement format and your accounting platform.

    Project stage: Onboarding

  2. Planning

    Discovery with the owner and the person who chases payments; quote structure, acceptance evidence, payment schedules, reconciliation rules and reminder cadence are written into the scope document.

    Project stage: Planning

  3. Design

    The acceptance screen and portal designed for a client on a phone; the quote builder and payment view designed for a desk, with the PDF templates matched to your brand.

    Project stage: Design

  4. Development

    Built in layers: clients, price list and quotes first, then acceptance and conversion, then payments, reconciliation and reminders, then credit notes, recurring invoices and the portal.

    Project stage: Development

  5. Client review

    A month of real quotes and invoices runs through the system in parallel with the old method, and payment matching is compared against the bank statement line by line.

    Project stage: Client review

  6. Revisions

    Changes from the review are made and re-checked against the scope document.

    Project stage: Revisions

  7. Ready for launch

    Open documents migrated and the sequence continued, the accounting export verified against a real month, reminder schedule tested on addresses you control, launch checklist signed off.

    Project stage: Ready for launch

  8. Delivered

    The business quotes, invoices, reconciles and reminds on the new system; hosting and maintenance continue under their own agreement if taken.

    Project stage: Delivered

Integrations

Commonly integrated

Systems this kind of business usually asks us to connect. Each integration is confirmed during discovery; none is assumed.

  • Accounting platforms receiving invoices, credit notes and payments
  • Card payment providers for payment links on invoices and deposits
  • Bank feed providers or statement file import for transfer reconciliation
  • E-signature providers where a separate signed document is required beyond on-screen acceptance
  • Email and SMS providers for quotes, invoices, receipts and reminders
  • Job management, scheduling or CRM systems that trigger stage invoices
  • Supplier price files for materials price lists

How we would approach it

Worked example

Concept demo

A fit-out contractor with site variations and retention

The situation

A fit-out contractor wants quotes assembled from a materials price list that updates from supplier files, variations agreed on site and signed on a phone as supplementary quotes linked to the original, stage invoices raised when a stage is marked complete in the contractor’s job system, and a retention amount withheld from each stage and invoiced on a date set at acceptance.

Why it is a custom build

The custom route is needed because supplier-fed pricing, linked variations and retention invoicing go beyond the fixed price list and deposit-and-balance schedule the package offers.

The scope we would propose

  • A price list import with change tracking so open quotes show where costs moved
  • A variation document type with its own acceptance and numbering tied to the parent quote
  • An interface from the job system that creates the stage invoice from the agreed schedule
  • A retention ledger per job that raises the final invoice when its date arrives

Concept demo: a scoping scenario written to show how we would approach the work. It is not a delivered client project.

Pricing

What affects the price

Every proposal is priced on scope. These are the factors that move it most for this kind of build.

  • Complexity of quotes: optional items, versions, variations and price list sources
  • Acceptance evidence required and whether a signature provider is involved
  • Payment schedule rules: deposits, stages, retention and recurring invoices
  • Payment providers and the reconciliation method for bank transfers
  • Reminder cadence, tone variants and whether statements are sent
  • Accounting platform and any job or CRM system to connect
  • Volume of clients, open quotes and unpaid invoices to migrate
  • Hosting choice: your own hosting or ours

Start from a package

Quote and invoice package

Quote builder with optional items and expiry, online acceptance with signature, conversion to deposit and balance invoices, payment links, bank transfer matching, credit notes, overdue reminders, branded PDFs and a client document portal for small businesses, trades and consultancies.

Custom build
View the package

FAQ

Frequently asked questions

How do you decide whether we need a custom build or the package?

During discovery we compare how your business quotes and gets paid against the quote and invoice package. If a maintained price list, on-screen acceptance, a deposit-and-balance schedule and standard reminders cover your work, we quote for the package. Supplier-fed pricing, variations on site, retention or stage invoices triggered by another system point to the custom route.

Does the system handle our tax?

It applies the tax treatment you set per line and shows it on the document. It does not decide what the treatment should be, calculate a return or submit anything; those remain with your accountant and your accounting platform, and the figures are your responsibility and theirs.

How are bank transfers matched to invoices?

Each invoice carries a reference the client is asked to use. Incoming transfers from a statement file or feed are matched by reference first, then by amount and date; anything that does not match cleanly is listed for a person to confirm, and nothing is marked paid without a match.

Is an on-screen acceptance enough evidence?

The system records the quote version, the options chosen, the signature drawn, the time and the network address, and freezes that version. Whether that is sufficient for your contracts is for you and your adviser to decide; a separate signature provider can be connected where a formal document is needed.

Who owns the system afterwards?

You do. The source code and your data are handed over at delivery. Hosting and maintenance are optional and separately agreed, and you can move the system to another provider.

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