Collections questions, answered plainly.

Usually after 60–90 days overdue, once reminders and a final written demand with a 7–10 day deadline have gone unanswered, and after any contract-required dispute or arbitration step.

Most work on contingency, commonly keeping 25–50% of what they recover. Older or smaller debts tend to carry higher rates.

For smaller invoices it often is: filing fees are low, you keep the full amount if you win, and you don't need a lawyer. Limits vary by state.

The contract or work order, the invoice, proof of completion, every message, your payment history, and your final demand letter.

Generally yes if your contract or terms include a late-fee or interest clause. Without one, many states allow statutory interest on overdue debts, but rates vary.

The rate in your agreement, as long as it stays under your state's usury cap. Without an agreed rate, state statutory rates commonly fall around 6–10% per year.

A rate added after a dispute starts is much harder to enforce. Put the rate and due date in writing before work begins and on every invoice.

When recovery would likely cost more than the invoice, or the debtor is unreachable or insolvent, and you've documented your collection attempts.

Often only if you already reported the income (accrual accounting). Cash-basis filers usually can't deduct income they never received. Ask a tax professional.

Yes. A write-off is an accounting entry; you can still pursue payment, file complaints, or add the invoice to a group claim. Report any later recovery as income.