I've tinned 24 awg stranded and, because of how thin it is / how few strands there are, I found that it snaps easily. Hence, why I now prefer solid for thin wire needs.
Regarding Fleabay - every seller is obviously different, but I bought wire twice from 2 different sellers and in both cases it was old or poorly stored, brittle and crumbly. Caveat emptor.
Any time you tin stranded wire, it is prone to breaking. The auto industry never tins or solders connectors for this reason. They crimp connections. One exception I found were BMW motorcycle harnesses. They bond multiple connection wires of the same circuit together inside a harness but only in a straight run. I think anytime there is movement or vibration, a soldered connector or wire end will tend to break.