https://lockmargin.com Practical guides and engineering notes on freelance invoicing, privacy, and offline-first software. Thu, 13 Aug 2026 05:57:57 +0000 en https://lockmargin.com/blog/freshbooks-3-year-cost.html https://lockmargin.com/blog/freshbooks-3-year-cost.html Sat, 08 Aug 2026 00:00:00 +0000 Learn how this applies to your freelance business. For freelancers who want to stay organized and in control of their data. https://lockmargin.com/blog/client-disputes-invoice-evidence.html https://lockmargin.com/blog/client-disputes-invoice-evidence.html Thu, 06 Aug 2026 00:00:00 +0000 Last year a client wrote me four words: "This invoice is wrong." Everything after that was decided by a folder on my disk, not by my mood. Here is the ... https://lockmargin.com/blog/database-corrupted-recover-history.html https://lockmargin.com/blog/database-corrupted-recover-history.html Thu, 06 Aug 2026 00:00:00 +0000 That line appeared on my screen on a Tuesday morning, eleven minutes before a client call. Everything after it was decided by one question: did I have a ... https://lockmargin.com/blog/how-to-invoice-without-internet.html https://lockmargin.com/blog/how-to-invoice-without-internet.html Thu, 06 Aug 2026 00:00:00 +0000 You are on a train somewhere between two cities. The signal died forty minutes ago. On your screen: a finished invoice and a client who needs it by six. ... https://lockmargin.com/blog/quote-vs-estimate-vs-invoice.html https://lockmargin.com/blog/quote-vs-estimate-vs-invoice.html Thu, 06 Aug 2026 00:00:00 +0000 A freelancer sends an invoice. The client replies, "Thanks, we'll consider it." Or sends an estimate and gets back, "Great, go ahead" — at a number that ... https://lockmargin.com/blog/should-i-encrypt-my-invoices.html https://lockmargin.com/blog/should-i-encrypt-my-invoices.html Thu, 06 Aug 2026 00:00:00 +0000 Most freelancers think encryption is for spies and people with something to hide. In practice it is for people with something to lose: a laptop, a backup ... https://lockmargin.com/blog/should-i-store-invoices-in-dropbox.html https://lockmargin.com/blog/should-i-store-invoices-in-dropbox.html Thu, 06 Aug 2026 00:00:00 +0000 After the backup article I keep getting the same email: "Vlad, I already pay for Dropbox. Can't the invoices just live there?" Short answer: yes, as one ... https://lockmargin.com/blog/signs-youve-outgrown-invoice-templates.html https://lockmargin.com/blog/signs-youve-outgrown-invoice-templates.html Thu, 06 Aug 2026 00:00:00 +0000 I made free invoice templates and published them for anyone to download. They get downloaded every week. And still I am writing the article about when ... https://lockmargin.com/blog/when-to-stop-using-spreadsheets.html https://lockmargin.com/blog/when-to-stop-using-spreadsheets.html Thu, 06 Aug 2026 00:00:00 +0000 I started with a spreadsheet too. It was the right tool for my first five clients. It became the wrong tool somewhere around client fifteen. I kept using ... https://lockmargin.com/blog/freelance-tax-deductions.html https://lockmargin.com/blog/freelance-tax-deductions.html Wed, 05 Aug 2026 00:00:00 +0000 April 2025. I'm sitting at my desk in Kharkiv, staring at a spreadsheet that looks like it was designed by someone who hates me. My tax preparer just asked ...