I like Odoo, but, there doesn&#x27;t seem to be enough glue in the Open Source release to do things like billing for services in a sane and coherent manner.<p>The UI for LedgerSMB is just horrible.  I don&#x27;t think it&#x27;s really been updated since 1999.<p>I really haven&#x27;t messed with ERPNext, mainly because I can&#x27;t get it to install correctly.<p>It&#x27;s my opinion that there really are not a lot of good, truly open source ERP&#x2F;Accounting systems for businesses out there.