For an affordable alternative, take a look at Simple Invoices. This invoicing tool lets you track clients, manage recurring billing, adjust tax rates, and more. And Like Freshbooks, you can access it from any Web browser.
Diagram creation: Dia
If you need to create flowcharts or other visual diagrams, Microsoft Visio is a great tool to use. It will also cost you $250 per license.
Instead, try Dia. Inspired by Visio, Dia includes a variety of tools and special objects to help create entity relationship diagrams, flowcharts, network diagrams, and more. It can also save diagrams in a variety of file formats, such as XML, EPS, WMF, SVG, PNG, and XFIG.
Adopting open-source solutions
Although open-source tools themselves are free, there are hidden costs you should be aware of. Whether you're starting from scratch or switching from an existing software tool to an open-source equivalent, there will be a learning curve to get comfortable with the new software. If you're transitioning from one tool to another, you may also need to find a way to convert or migrate data from your existing programs.
Also, most open-source projects have robust communities of supporters willing to help and share knowledge, but you won't have a vendor to call when something goes wrong. Some open-source projects or IT companies do provide support for open-source tools for a fee— but then that defeats the purpose of choosing open source in the first place, doesn't it?
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