As of now, I am planning to apply to 6 prelim programs (in one city). Is that enough? Also, if I were to apply to transitionals and prelims within the same program, would there be 2 separate interview dates?
*some* prelim/TY programs will interview you once, and you can just rank-list both prelim/TY in ERAS. youl'l have to ask each program
if you have $ and time, i'd interview at more than 6 since prelim/TY can be competitive. you'll be up against some well-qualified dermies, ophtho, rads, etc.