help, does anyone know if these routers exist??

Hi guys, first time post, please excuse my mistakes

so I'm moving into this apartment with 2 other ppl. We got 3MBps Cable internet.

the other two guys are not very good with computers, but they use stuff like AIM/ MSN/ and P2P programs alot. They also have a tendency to keep the computers on w/ these programs running.
I am pretty good with computers and likes to play multiplayer games online.

I know that those two are going to hog up most of the bandwidth just b/c of their neglect and lack of knowledge in how to maintain their windows operating systems. Also i'm pretty sure they have spyware and adware running that is hogging bandwidth.

So my question is that is there any routers that I can buy that has good performance, but also can let me limit each user's bandwidth? such as by IP address, which i can assign to their computers, or some other way?? I know the Dlink Gaming router has the QoS thing, but it is only for upstream... and downstream is a big problem.
the router also needs to have good wireless capabilities, so everyone can get internet in the whole apartment.
money is not a big problem unless those routers cost like 500+. I'm not looking for huge server/datacenter class routers :-p

Thanks very much,
mikey19