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

In five weeks I'll be moving our stuff from storage to a new house.  My audio room is the "bonus room" above the garage, about 15 steps up from the main level.  My amp weighs 110# out of the box, speakers are 122# and subwoofers are 133# each.  I've hired movers and walked thru the move with the owner, so he'd understand what's involved.

After the boxes are hoofed up the steps, getting my son & son-in-law to help me unbox the components and get them up on the stand.

I guess the next step is an appointment with an orthopedic surgeon?

I agree with those that suggest a hand cart that's made to climb stairs. As suggested one or two additional straps are necessary to keep the item being transported in place. My hand cart has an additional extension that folds down increases the size of the platform from 18" wide x 6" long to 22" long. I've used this to move heavy amps and very large, heavy speakers up and down long flights of steps. No problem. It's surprising how you will use it for moving many other items at home etc.

My friend got a hernia from helping me move a Mark Levenson 336 up 2 flights of winding staircase.

Be wise hire a mover.

Best of luck!

Longer this thread goes, with all good suggestions, more correct geoffkait seems to have been. (Sell the amp, buy a Discman.)

https://www.collegehunkshaulingjunk.com/labor/

(no matter what they charge, it is worth it)

Dolly with padding and straps or duct tape. I don't know how any household does not have a dolly.