This is (IMHO) a classic “Nehurah Bei Planya” question and therefore Avak Lashon Hara to answer regarding specific areas. Go, do your Hishtadlus, and if you have a good cause, may Hashem help you.
One point. If you go Purim night, do not expect anyone to open doors. People want to sleep and there is no Chiyuv.
For whom are you planning to collect?
lesschumras – It says on Purim “Kol HaPoshet Yad Nosnim Lo”, which means you have to give something. 10 Agurot or a penny is “something”, and they get the point.
I have also heard that many “wealthy” people go away for Purim, so don’t expect anyone to respond. Even without people knocking for money, it may be cheaper than having to give so many Mishloach Manos LOL.