The operations layer for the solo accountant running a portfolio like a firm twenty times her size.
Flat-fee, AI-first operations layer for solo accountants and small professional service firms. Client portal, AI document collection, branded client reports, and a compliance + invoice workflow — bundled for the solo accountant who today still stitches the same five tabs together.
Starting around $99/mo flat — no per‑seat, no per‑document upsell, no "enterprise tier required."
Four fires, one operator, held together by memory.
The work between “new client” and “paid invoice” is the same four drains, repeated every engagement: intake, engagement letters, document chasing, and compliance. Plumbmark folds them into one operations layer.
- 01
Client intake
A new client emails "I'm ready." So you spend the next two hours rebuilding the same intake checklist from memory and pasting it back.
- 02
Engagement letters
Drafting the engagement letter, getting it signed, and storing it on file is a separate tab every time — and the audit trail lives in your inbox.
- 03
Document chasing
Half the year is reminding people to send the W‑2, the K‑1, the 1099, the bank statement — the same message, sent six times, six ways.
- 04
Compliance
KYC, AML, IRS filings, and state‑bar requirements are a checklist you keep in your head until the week a regulator wants to see it.
Three things, one flat fee.
No five‑module sprawl. Plumbmark bundles the three surfaces a solo accountant reaches for every engagement — and bundles them so they share one workflow, not five logins.
Built for the firm of one. Priced for the firm of one.
We're onboarding a small first cohort of solo U.S. tax and bookkeeping operators. Drop your email and we'll be in touch when an early‑access seat opens up.
No spam — we'll only email about early access.
Rather talk to a human? Write plumbmark-u07h6r@polsia.app.
See Plumbmark for your practice
See the three flat‑fee tiers, or read how Plumbmark handles AI document collection for each solo vertical we serve.
Privacy & data handling
Plumbmark stores uploaded returns, contracts, and engagement packets in the U.S., segregated per firm. Document intelligence calls do not train third‑party models on your client's records. A SOC‑2 path is on the roadmap.