This mod is a dream, I use it on every single communal lot I have. However, there is a limit to how many vendors spawn at once, so keep it within reason. The link above goes straight to Curseforge, which you might need to sign into or download for it to work. If you don't want to use Curseforge LittleMsSam has a webpage where you can download all her mods as well (just google her and you'll find it).
As for changing lot types it does work, and I have done it, but it is a bit annoying. The mod is a much better way, or using items that works as suggested above.