used rotel amp

I am wanting to purchase a used amp (that is about the same price as a couple refurbished parasounds HCA855 or adcoms 7300 with 1-2 year warranty), it is about 3 to 4 years old. It is a multi-channel amp that is thx certified. What kind of life would I expect out of a used amp? 3 to 4 more years? Are they expensive to repair?

If it is just 3-4 years old now, I'd be surprised if it didn't last more than another 3 to 4, at least under normal usage conditions. Rotel enjoys an excellent reputation for reliability. Cost of repairs would obviously depend upon the problem, but I wouldn't expect exorbitant repair costs, again for a "normal" problem.
Rotel amps are very reliable and well made. If not abused expect a long sevice life.
Someone snagged the Rotel before I could buy it, so I ended up buying a 3 channel acurus A100X3 amp. My fiance liked the looks of this amp a lot more even though I told her I would have to buy another 2 channel to complete it. So now I need to get cables. I have the same Klipsch and Denon as listed above. I have tried MIT and liked there sound. The guy I bought the amp from recommended a guy who does custom canare cables in the $40-60 range. I also ran accross the outlaw cables which sell in the $30 range that looked like they were made rather well. I am wanting a warmer cable more like the cardas and less like the kimber pbj. I dont want to go bright or else the horns in the klipsch will go crazy.