A mechanic's lien is not a substitute for a clean accounts-receivable record. It is a legal remedy that depends on the project, the state, the type of work, the required notices, and the dates that prove when labor or materials were supplied. The safest operational habit is to treat every unpaid or short-paid invoice as a clock with an evidence trail, not as a single overdue balance. The evidence trail usually starts before the lien filing itself. Keep the signed contract, schedule of values, change orders, pay applications, portal receipts, rejection notes, conditional waivers, and bank confirmation together. A portal status that says Accepted only proves the file arrived; it does not prove approval or payment. Comparing that status with the QuickBooks invoice is how a quiet underpayment becomes visible while there is still time to act. Deadlines vary by state and by project type. The claimant's role, direct or lower-tier contract, public or private project, residential exception, payment bond, last labor or delivery date, notice recipient, service method, and any notice-of-completion or contest procedure can change the result. Drumtap does not give legal advice or file a lien. It helps organize the underlying reconciliation so you and your counsel can see the amount, the missing document, and the relevant date before the window closes. Start with the prompt-payment and lien-rights guide , then compare the portal reconciliation workflow with the records you already keep. The legal decision stays with you and your attorney; the evidence should be ready before the deadline makes the decision urgent.