I recently bought a house, and would like to add a bit of character to the home. I really like the look of knock down texture. I have absolutely no experience in home repair as this is my first home of my own. Everything I have seen since starting to research how to do this, shows or talks about doing this with an unfinished wall. My questions is are there any other steps or things to consider other then the obvious covering the carpet and getting furniture out of the room when wanting to do a large project in a finished House. All the walls are just painted and for the most point my walls are in great shape but have found a few places where looks like where two pieces come together there is a gap, can that be fixed by sanding, taping, then mud and sanding. like how it would be done when being installed? And one last thing my bathroom does have a light texture to the walls looks like it may be sand texture, any thing there need done to prep that wall to knock down? I know there is a lot there but any help would be greatly appreciated. Thanks!!

This may be a stupid question but, what is the standard length of a wood stud for an 8 ft. wall? ... a 10 ft. wall?