Maybe I can help with your project.
I wrote a custom GL intranet site with PHP + SQLite (easily movable to MySQL) that mostly overlaps your GL requirements, but as you are budget constrained, I would offer only to implement your top priority features.
I can also look at your existing loans app and make the easy updates for a symbolic fee. Or, if there are high priority items that require serious work, maybe we could negotiate out a deliverable with both modules combined.
Drop me a line thru Chat if you would like to discuss further; I can show images of my GL script or arrange for a demo. Thanks for your attention anyway.