Apartment 12 (2001, R)

I imagine this film would have had the more lenient rating of PG-13 if it had been released through a larger production studio (it has sex, but not really any nudity, no drug use, and there was some language but not pervasive throughout the film).  It stars a younger-looking Mark Ruffalo (The Avengers, The Brothers Bloom) as an (aspiring) artist whose girlfriend breaks up with him and kicks him out of their apartment (so that he must rent a new apartment... guess what the unit number is).  Granted, we don't see a lot of their life prior to this point, but the reason for Yvette (ex-girlfriend) kicking ending their relationship is unclear, enough that Ruffalo is blindsided by it.  For the early part of the film, all of the small and medium-sized things go wrong with his life and it was amusing (as opposed to Spider-Man 2, druing which I expected Parker to compulsively harm himself).  His new apartment building is like an Island of Misfit Toys which I often like in stories (like the 2004 Punisher film).  The film follows him in his pursuit of creating art and finding companionship.
  I liked that the very first scene(s) were pretty good at establishing what was going on with the characters in very little time but without feeling rushed (that's a bit of a feat).  Much of the film after that was a bit slower, but it's just a normal indie ride.  Also amusing, is the fact that several of the cast are credited as "Pretentious Artist" or "The Other Suits".

If you liked Art School Confidential, I think you'll like this movie.  It's sort of a quarter-life crisis (like Clerks) movie about an artist type, and so if you're that type then this movie could be up your alley.  It's not uproariously funny, but it had enough laughs and amusing moments to keep me interested.  For me this movie was about 3.5 stars.  If you like this movie, be sure to watch through the credits as well because they show a few deleted scenes therein (including the "avant garde" scene, which you'll notice is missing in the body of the film but can livc without if you have to).  And I mean all the way though the credits (there's one after it's completely over, though most of them are in the first half and you can tell when they're done).  I imagine most of these scenes were cut for time rather than for content, as they seem to fit pretty well with the rest of the film and you can tell where they would likely have been inserted.