I dunno, man. My wife *really* enjoyed helping me muscle the Whirlwind, Earthshaker, and Terminator 2 upstairs... 8-P
I promised she'd never help me move them again after this. We're both partially-crippled, and it took two days, two machines the first day, one the second, pulled some muscles, but they're up there, no gouges in the walls/handrail, either. Never felt like I'd lose them, either.
Funny thing was, she was below, pushing and said, before we started the first one, "I'll catch it if it starts to fall."
I explained, "Sweetie, if you hear me say, RUN, you get to the bottom of the stairs as fast as you can, around the corner, so if I drop it, at least you have a couple of wall studs between you and what will likely kill you if it falls on you."
She understood, when I put it that way.
What's more amazing is she's helped me move those machines from Bailey, CO, to Portland, OR, then to Austin, TX, and finally to Fort Worth. Neither of us are young, either, but determined? Yeah. Stubborn, too.
No problems doing it, but it was far from enjoyable. The aluminum handtruck was a really good purchase. Used to move them by carrying them, which amazes me, now.