Replying to Studio appartment audio

I'll keep this short:

I'm soon moving into a studio style apartment, but I wont have any neighbors I would piss off with a big sound system.

I have about $250 to spend, and I already have a nice pair of Boston acoustic bookshelf speakers.

I'm going to use it for everything, wired to my computer and tv. I listen to a wide variety of music, and want it to sound good for movies.

So, within budget can you recommend me a sub, some floor speakers, and maybe a sound-bar/ more bookshelf speakers?