[August 2025 Update] Homeowners keep asking for upgrades mid-job, and subsidies like MaPrimeRénov' continue to shift through 2025. That means more scope changes, mixed VAT rates (10%, 5.5%, 20%), and tighter margins. Materials still move with the BT01 index, and clients compare every quote. Stay sharp: price changes fast, get approvals in writing, and bill without delay. For subsidy details, check France Rénov'. For macro trends like BT01, see INSEE.

This article gives you a simple 72-hour change order system you can run on every job. Plain steps, ready-to-use scripts, and how to handle VAT lines. We show exactly where a tool like Donizo fits so you save time and protect your margin.

The real problem: free work and slow cash

• Client says, "While you’re here, can you also…?" You say yes. No paper trail. Weeks later, they forget it was extra.
• Plumber moves a drain. Painter does an extra room "quickly." Tiler shifts a layout. No signed change. No deposit. You just donated your Saturday.
• Mixed VAT jobs add risk: energy upgrades at 5.5%, renovation at 10%, sometimes 20% on new area. One mistake and there goes your profit.

Stop the free work with a clear, repeatable system.

The 72-hour change order system

1. Capture the ask on site

• Take a photo and dictate the change by voice. Keep it specific: scope, location, materials, and what’s excluded.
• Example: "Add one extra double socket in living room, right wall, finish same as existing. Does not include repainting whole wall."

2. Price the change the same day

• Use a quick cost sheet. Add your margin, then VAT.
• Guardrails help. If you aim for 35% margin:

Selling price = Cost / (1 - Target margin)
Example: Cost €400, target margin 35% → 400 / (1 - 0.35) = €615.38

3. Choose the right VAT per line

• 10% for most renovation in housing older than 2 years.
• 5.5% for energy improvement lines (insulation, efficient heating, certain controls) when eligible.
• 20% for new construction, added floor area, or non-eligible cases.
• When in doubt, check Service-Public: TVA travaux dans les logements and ask your accountant.

4. Send a clean change order with expiry

• PDF/proposal with line items, VAT on each line, total incl. VAT, and a 7-day validity. Make it e-sign friendly.

5. Get money aligned with work

• Ask a deposit for larger changes (e.g., 30–50%) or add it to the next progress invoice. No approval, no extra work scheduled.

6. Follow up at 24h and 72h

• Quick reminder wins jobs. Keep it short and friendly.

On-site script

"Happy to add the extra outlet. I’ll send a small change order today. Once you approve it, I schedule it and we get it done."

SMS template (24h)

Hi {FirstName}, here’s the change order for the extra {work}. Total incl. VAT: €{amount}. Valid 7 days. Approve here: {link}. Any questions? Call me.

Email subject lines

• Change order attached — quick approval to lock your date
• Your extra works quote (valid 7 days)
• Follow-up on the change you requested

Do this in Donizo (fast and painless)

Use Donizo to run the whole flow:

• Dictate the change by voice → Donizo drafts the line items.
• Set 5.5%, 10% or 20% VAT per line. Totals are automatic.
• Send a professional proposal with expiry and follow-up reminders.
• Convert approved changes into an updated project and invoice in a click.
• Track who still owes what, see status at a glance.

Mixed-rate example: keep it clean

Line items (example):
- Supply thermostatic valve — 5.5% VAT
- Replace vanity cabinet — 10% VAT
- Move drain for new shower — 10% VAT
- Build new partition (new area) — 20% VAT

Tip: mention assumptions in the notes. Example: "Partition excludes painting. Painting can be added as a separate line if requested."

Make billing boring (that’s a good thing)

• Always take a deposit on material-heavy changes.
• Use progress billing for larger jobs. Issue partial invoices when milestones are hit.
• Send friendly reminders at 3, 7, and 14 days overdue. Keep it human, not hostile.

Reminder script

Subject: Quick nudge on invoice {#}

Hello {FirstName},
Just a quick reminder on invoice {#} (€{amount} incl. VAT). Can you settle it today? Here’s the link: {payment_link}.
Thanks for the quick action so we can keep your schedule on track.

Donizo keeps the cash moving

With Donizo:

• Generate invoices with correct French VAT (20%, 10%, 5.5%).
• Request deposits and issue progress invoices in a couple of clicks.
• See payments, balances due, and automatic follow-ups.
• Centralize client messages and site notes so nothing gets lost.

Quick checklist you can print

• Capture change by voice + photo
• Price same day (use margin formula)
• Set VAT per line (5.5% / 10% / 20%)
• Send proposal with 7-day validity
• Collect deposit or adjust next invoice
• Follow up at 24h and 72h
• Don’t start extra work without approval

Why this matters in 2025

• [August 2025 Update] Subsidies like MaPrimeRénov' keep changing. Clients tweak scope to chase incentives. More changes, more risk.
• Prices shift with BT01. A 2-week delay can erase your margin if you don’t lock approvals and deposits.
• A simple system beats memory and WhatsApp threads.

Final word (and a tool that helps)

Do the change in 72 hours or it drags forever. Keep it written, priced, signed, and billed. That’s how you protect your time and margin.

Try this workflow inside Donizo — voice quotes, proper VAT per line, proposals, invoices, payments, and project status in one place.

Disclaimer: This article is practical guidance, not tax advice. Always verify VAT eligibility and documentation requirements.