Short answer
Interior designers use Sign PDF to send a letter of agreement for the design fee, then a short purchase approval for each order of furniture, fabric or lighting, which the client signs on their phone. Custom pieces are usually non-refundable once ordered, so the signed approval is your record of who agreed to that.
Updated 25 October 2026
What goes in an interior design letter of agreement
Designers call it a letter of agreement, a design contract or a proposal; legally they do the same job. It sets out what you will design, how you charge, and what happens when the client wants more than they bought.
- Phases: concept, design development, procurement, installation, styling.
- Fee model: flat fee, hourly, percentage of project cost, or a mix, such as flat for design and hourly for project management.
- Rounds of revisions included, and the rate after that.
- Procurement terms: net trade price plus a markup, or cost plus a fee, and whether you disclose trade discounts.
- Exclusions: structural, electrical or plumbing work and permits, which need other professionals.
- Ownership of drawings and the right to photograph the finished space.
A purchase approval for every order
The letter of agreement covers your fee. The money that causes disputes is the furniture. Send a one-page purchase approval listing each item, the finish, lead time, price and deposit required, and say clearly that custom items cannot be cancelled once ordered.
Two clients often share the decision. Add both, set them to sign before you, and the sealed PDF shows each of them agreed to the $4,200 sofa in that particular velvet.
Portfolio photography
If you plan to photograph the finished rooms for your website or a magazine, get permission in writing. A separate yes or no checkbox in the agreement, or a short photo release, is clearer than a line buried in clause 14. Clients who say no to their address being published should be able to say so.
Contractors and trades on a design project
When your scheme needs a joiner, a decorator or a kitchen fitter, decide early who contracts with them. If the client does, say so in your letter of agreement and make clear you are not responsible for their workmanship. If you subcontract them, you need your own written agreement with each, covering price, schedule and who fixes defects.
Either way, a signed quote from each trade, approved by the client before work starts, keeps the budget honest. Send it through Sign PDF with the client as signer, and keep the sealed copy with the project file.
Plans and what we do not handle
Purchase approvals add up quickly on a full-home project, so most designers choose Full at $10 a month for unlimited documents and templates. Light at $5 covers 2 documents a month, which suits e-design work where only the agreement needs signing.
We do not run product boards, client portals, invoicing or payments. Keep your design and project software; send the signatures through us.
Questions people ask
Can I send a mood board or floor plan for the client to initial?
Yes. Upload the PDF and type 'client initials every page'. The initials and date boxes are placed for you.
Can I send a purchase approval from my phone at a showroom?
Yes. Upload the quote or a photo of it, add the client's email and send. They sign on their own phone.
Does Sign PDF collect the client's deposit for furniture?
No. We do not take payments. Invoice the deposit from your accounting tool after the approval is signed.
Can I reuse my letter of agreement for every new client?
Yes, on the Full plan. Save it as a template and only change the names, rooms and fee.
Send your next letter of agreement: living and dining rooms for signature
Upload it from your phone or laptop. The boxes go in the right places, your client signs on their phone, and you get a sealed copy back.
Upload a document