I guess you might be eating this and calling it a learning experience.
It does point out the need for well defined scope of work in any agreement, written and signed.
BTW these days recording these verbal agreements is fairly trivial I imagine ("pen" recorders, smart phones etc). Just be sure you disclose it is being recorded before you do it, that is law in a lot of places.
It can be as simple as just saying "OK I am recording this so I don't forget to do anything we agree on" and then identify the parties, date, lay out the scope of work, the terms and have them agree.
