newbie with old questions

Hi all. Looks like a great site. I did do a bunch of searching but it can get confusing with all the different questions versus answers.


I am currently renovating my main bathroom. the house is OLD with many add ons. The main sewer line is 3" pvc gong to the street with a 2" vent thru the 1st floor to roof. it was boxed in. i am now moving it inside a wall and i want to know if the vent can make 90s. does the vent need to go straight up or can i do a few angles to it to keep it in the walls?
Also i would like to know a basic rough in for a bathroom sink drain. Dont know what type of sink yet but i'm going with basic vanities. Is 20" on center good?
thank in advance

vent

A vent can be run anyway you desire, or have to, as long as it keeps going upward. 20" is adequate for a "normal" lavatory, but I prefer 17", because someone can always come up with one that is not normal.