If you can't lift 100 lbs by yourself - then you need another person besides wifey/gf/daughter who is strong enough and won't drop it. I once tried to take a Proceed 5 ch amp (~100 lbs) up a floor. The problem with the amp was that all the weight was in the front and it almost took my toe off, luckily I was able to slowly lower the amp to the floor without damaging it. Amps that weigh ~ 100 lbs are meant to be stationary. Handcarts etc can be handy, but if it rolls own the stairs and knocks your granny over, its pretty much over.
