Sieve - Easy sorting, filtering and pagination for .NET core
Invoice Ninja - Invoice Ninja is a free, open-source solution for invoicing and billing customers.
Freelancer Stack - Curated directory of tools used by 10,000+ freelancers
Harvest - Simple time tracking, fast online invoicing, and powerful reporting software. Simplify employee timesheets and billing. Get started for free.
Freelance Rate Explorer - Visualize rates for thousands of freelance designers & devs
GnuCash - A personal and small-business financial-accounting software, licensed under GNU/GPL and available for Linux, Windows, Mac OS X, BSD, and Solaris.