The KRKs are great, I use that model for production but they won't be enough for a party.

For PA ideally shop around for 2nd hand Mackie, or failing that JBL and RCA do pretty decent powered monitors.

If you have to have loads of power on a budget you could go for Behringer, KAM or Soundlab but you'll be buying budget stuff. Will be noisy - depends where your priorities are.

Basically if you want decent sound and quality budget a pound a watt.

If you want cheaper, you'll have to compromise on either sound quality or power rating.

Other thing to bear in mind is that cheap stuff usualyl over rates its perfomance, with new buyers in mind. 700W sounds impressive, but it often doesn't mean much as the sound pressure will depend on the drivers, the build of the cab, the quality of the amplification etc etc.

How much have you got to spend?