A boiler replacement isn't a one-payment job. You quote the work, take a deposit for materials, possibly take another payment when the boiler arrives, then invoice the balance on completion. That's four separate financial interactions — and most engineers manage it with a notepad and a calculator.
GasVault handles the entire payment lifecycle in one place. A quote converts to an invoice with one tap, receipts are linked to the original quote, and the final invoice automatically calculates and displays every payment already received, leaving just the balance due.
The Full Payment Flow
Create a Quote
Build a quote with line items — boiler supply, flue, labour, disposal. Load from a template or add items from your price book. Send as a PDF via email or WhatsApp directly from GasVault.
Client Accepts
Mark the quote as Accepted. Three action buttons appear: Take Deposit, Record Payment, and Create Invoice.
Take a Deposit
Tap Take Deposit. A receipt form opens pre-filled with the client details and quote reference. Enter the amount and description. GasVault generates a professional receipt PDF — numbered REC-0001 — which you can email immediately. The receipt is automatically linked to the quote.
Record Stage Payments (Optional)
If the client pays for materials before the job or makes a further payment mid-works, tap Record Payment. Same process — receipt generated, linked to the quote, another numbered PDF receipt sent to the client.
Create the Final Invoice
Tap Create Invoice. GasVault opens the invoice editor with all quote items pre-loaded. You can add any additional work carried out. Tap generate — GasVault automatically fetches every linked receipt, deducts them from the total, and shows the balance due. One PDF, complete payment history.
What the Final Invoice Looks Like
Here's an example for a boiler replacement job where a deposit and a materials payment were taken:
The client can see exactly what they've paid and what's outstanding. No confusion, no disputes about whether the deposit was taken into account.
Standalone Receipts
Receipts don't have to be linked to a quote. Sometimes a client pays cash upfront without a formal quote — for a repair callout or a small job. In that case, open the Receipt form directly from the dashboard, enter the client details manually or select from your database, add the description and amount, and generate the receipt. It gets its own number (REC-0003, REC-0004 and so on) and a professional PDF is ready to email in seconds.
Quote Templates
GasVault includes pre-built quote templates for the most common gas engineering jobs:
- Boiler Service
- Boiler Replacement
- Gas Safety Inspection (CP12)
- Power Flush
- Radiator Installation
- Gas Leak Investigation & Repair
Load a template and the line items and job description are pre-filled. Edit the quantities and prices, and the quote is ready. You can also save your own templates for jobs you do regularly.
AI-Assisted Quote Conversion
When you're ready to convert a quote into an invoice, GasVault's AI can rewrite the line item descriptions from future tense ("To supply and install") to past tense ("Supplied and installed") automatically. This is a small thing but it matters — an invoice should describe work done, not work planned.
Discount Support
Quotes and invoices both support discounts — either as a percentage or a fixed amount. The discount is shown as a separate line item on the PDF, which keeps the pricing transparent for the client.
The Numbering System
Every document gets its own auto-incrementing number:
- Quotes: QT-0001, QT-0002…
- Receipts: REC-0001, REC-0002…
- Invoices: INV-0001, INV-0002…
Numbers increment only when a document is finalised, not when drafts are saved. All documents are stored in the cloud and accessible from History on any device.
Try the full payment workflow on your next job
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