i suggest you on microniche with minisites.. with few competitor but huge market ( never thought something like excessive sweating disorder actually has huge market?
) .. put clickbank, proper placement of adsense, privacy policy, original contents and there you go..
for promotion you can go with various technique like article submission ( yes it's still works ) and link building, expect for high ranking on google, well you can earn at least $1/day .. multiple this by 100 minisites..
oh gosh i have lots in my mind, but i run out budget by spending too much on research tool like market samurai ( yes it can find micro niches ) .. so until i filled out my pocket again i can't make a move..
except if someone offering me a JV..