How to physically move large heavy 100lb amplifiers easily (up and downstairs)

Ideally with only one person, but even with 2 especially if there are stairs involved, how can I move this gear without breaking my back or hurting myself?
I actually have 100lb Emotiva XPR-1 amps that I move around when I rebuild them.  I use a standard hand-truck, but put a small hand-towel on the bottom plate.  Tilt the amp on so that it is on it's side and wiggle it onto the towel.  Strap the amp to the hand-truck if necessary. 
Hah, I watched those videos imhififan.  There was another video that came up just after it:

The Northern tool 3-wheel type can help climb stairs, but it appears that it's harder to turn/rotate this type of hand truck.  A hand truck with big tires and sliders appears to work better overall.  An example:

Used this to move 200lb+ Wilsons and Egglestonworks up 3 flights of stairs (27 steps). You’d still need 2 people (one to pull, one to make sure it wouldn’t go backward) and some ties.

The base of this cart is pretty wide.

IMHO way better than hiring 2 kids + $20 and have their backs injured, and/or drop your stuff.