Example 1: Plumber – boiler swap + small new loop=

• Replace an old boiler with a new high-efficiency unit installed in a 10-year-old house → 5.5% on unit + labor.
• Add a new heating loop= for a new extension area → 20% on that part (it’s new build/extension).
• Minor repairs on existing radiators → 10%.

Result: three lines, three rates. You protect your margin and stay compliant.

Example 2: Painter – interior repaint + supply-only paint

• Interior repaint in a 15-year-old flat → 10% (materials + labor if you install/apply).
• Client asks you to leave extra paint buckets for later DIY → those extra supply-only buckets are 20%.

Result: split lines. Don’t let a couple of buckets sink your pricing.

Scripts to get the client attestation signed

Use these word-for-word:

• Before quote approval: "To apply the reduced VAT, the tax office asks for a simple attestation that the home is over 2 years and that we’re doing eligible work. I’ll send it now — it takes 2 minutes to e-sign."

• Before ordering materials: "I’ll place orders as soon as the attestation is signed. That way your invoice stays at 10%/5.5% and you save money."

Set it up the right way in Donizo

Do this once, and you’ll stop guessing every time:

• Create the quote by voice in Donizo and speak the lines as you’d say them on site.
• For each line, pick the VAT rate (20%, 10%, 5.5%). Add a short note like: "Eligible housing > 2 years; repaint; installed by contractor."
• Attach or request the client attestation from the client record. Keep it tied to the project.
• Convert to invoice in one click. Donizo keeps the correct VAT per line.

Example invoice lines (split by VAT):
1) Supply + install high-efficiency boiler — 5.5%
2) New heating loop={true} in extension (PEX + labor) — 20%
3) Flush + service existing radiators — 10%
4) Extra paint (supply-only, left on site) — 20%

Cash flow + follow-up without drama

• Ask for a deposit (30–50%) tied to the right VAT on the deposit invoice.
• Bill progress by milestones (e.g., demo, first fix, second fix, finish). Keep VAT per line.
• Use Donizo to track who paid, who’s late, and send one-tap reminders. No chasing through texts and notes.

Pro move

• When a client adds extra tasks mid-job ("since you’re here…"), create a new line with the correct VAT and send a quick approval message from Donizo before doing the work.

Common traps and quick fixes

• One rate for the whole invoice: split lines. Always.
• Reduced rate on supply-only items: supply-only is 20%.
• No attestation: don’t apply 10%/5.5% without it. Send it for e-sign.
• Mixed energy/regular work dumped into one line: separate 5.5% from 10%.
• Verbal changes: add a signed note or quick add-on approval from Donizo.

Keep it simple, keep it clean

• Decide the rate by the job type, not by habit.
• Separate lines by rate with a short reason in the text.
• Collect and store the attestation.
• Use your tool to lock this down every time.

If you want to stop VAT guesswork and paperwork ping-pong, run your next quote and invoice in Donizo. Voice to quote, correct VAT per line, client files in one place, and payment tracking that actually helps you get paid.

Wrap-up

Mixed VAT is normal in renovation — the only problem is mixing it up. Split lines, get the attestation, protect your margin.

Ready to make it routine? Start your next job in Donizo and keep your admin tighter than your joints.