undergroundskate

I'm looking at buying some RF-7s and I don't know how much power to give them. I don't want to spend a lot of money on a high-end amp and I will probably go with a Yamaha/Denon/Sony stereo receiver. From what I've heard, it is easier to damage speakers by not giving them enough power, more so than overpowering them. What should I be looking for in wattage? I also considered getting a multichannel receiver in case i want to add surround sound at a later date. Any advice?