Interior Design Business Invoicing App (2026)
Design billing has two halves that must never mix: your fee, drawn against a retainer, and furnishings the client pays for in advance. ShowTheReceipts ($15/mo) invoices the retainer and shows the remaining balance on every invoice, bills flat phase fees, site visits, and extra revision rounds, and keeps furnishings and procurement on their own advance-paid invoices.
How we picked
Entry-plan prices as published in 2026, taken from each vendor's own pricing page or a recent third-party summary. Judged on the solo designer's billing workflow — retainers with visible draw-down, flat phase fees, site-visit and revision lines, and furnishings invoiced separately in advance with a stated procurement fee — not on 3D rendering, CAD specification, or multi-designer studio resource planning.
| Software | Starting price | Best for |
|---|---|---|
| ShowTheReceipts That's us | $15/mo | Solo interior designers: retainers with draw-down shown, phase fees, site visits, furnishings invoiced separately |
| HoneyBook | $29/mo+ | Contract-and-invoice client flow for creatives |
| Ivy (Houzz Pro) | $85/mo+ | Design-specific product sourcing with billing attached |
| FreshBooks | $21/mo+ | Invoicing bundled with small-business accounting |
| QuickBooks Online | $38/mo+ | Full accounting for a firm with a bookkeeper |
Two ledgers, never mixed
Your fee is one thing. The client’s furniture money is another — and it should never touch your credit card or your fee invoice.
1. ShowTheReceipts — $15/mo
Retainer invoiced up front with the remaining balance shown on every invoice, flat phase fees, site-visit and install day rates, revision rounds beyond the included count billed hourly, furnishings on separate advance-paid invoices with procurement stated as cost-plus or a flat fee.
2. HoneyBook — $29/mo+
Contract-and-invoice client flow for creative service businesses.
3. Ivy (Houzz Pro) — $85/mo+
Design-specific product sourcing with billing features attached.
4. FreshBooks — $21/mo+
Invoicing bundled with small-business accounting features.
5. QuickBooks Online — $38/mo+
Full accounting, aimed at a firm that has a bookkeeper.
The lines a design invoice needs
- Design retainer — paid up front, drawn against
- Hours billed / balance remaining — shown
- Flat phase fee — concept, development, documentation
- Site visits and install days — per visit or day rate
- Trade coordination — contractor and vendor management
- Extra revision rounds — hourly, beyond included
- Furnishings and procurement — separate invoice, in advance
Procurement is hours, not a markup
Sourcing, ordering, tracking, freight claims, receiving. State the cost-plus percentage or flat fee on the invoice — a markup discovered later costs you the client.
Frequently asked questions
Can it show the retainer balance on each invoice?
Yes — each invoice shows hours billed this period and the remaining retainer, e.g. '$4,200 retainer, $2,750 remaining.' That single line answers what the hours went to and triggers replenishment before you're working unpaid.
Can furnishings be invoiced separately from my design fee?
They should be, and they are — furnishings go on their own invoice paid in full in advance, with procurement stated as cost-plus 20–35% or a flat fee. Mixing them makes your design fee look like a rounding error next to a five-figure order, which invites discounting.
Does it handle revision limits and site visits?
Both are saved lines — included rounds per phase with your hourly rate beyond them, plus per-visit or day rates for site visits, install days, and trade coordination. Those are the hours most often given away on a renovation.
Is this a rendering or specification tool?
No — 3D rendering, CAD, and spec documentation are a separate category and you'll keep whatever you already draw in. This is the money side: retainers, phase fees, procurement, and furnishings paid before the vendor order goes in.