Is this possible?

I work as a leasing manager at a very upscale apartment complex and we are creating a home theater room with a 10 foot drop-down projection screen and seven in-ceiling speakers with two in-wall subwoofers. The installers came today to install the amps which turned out to be a Denon AVR-1082 which has 7 channels at 150 watts into 8 ohms. The installer said that the subs were not self powered and he would power them from the receiver. I can only assume that he will splice the rear channels and power the rear 4 speakers off of 2 channles and use the other 2 channels of surround amplification to power the subs. Doesn't this sound like it will create havok on the receiver with the ohm loads? This couldn't possibly result in 7 channel surround more like 5 channel with 7 speakers right? Does anyone know if there is a setting on the 1082 that could have it power woofers or is this guy gonna try and power subs off ofa surround signal and if there is no crossover won't that damage the subs? Is there some kind of setting that will allow those extra channels to only send LFE output? I think this installer is really shady since he claimed that the 1082 cost 2 grand but I know it is discontinued and the MSRP on it used to bu under $1000. Can anyone verify if this is possible or if we are being ripped off.