Washing machine up first floor maisonette (no lifts)

TELLIT01

three wheeler arrangements definitely help.  It's still heavy but moves up each step much more smoothly.  Still not a job for one person to try on their own.

FaceHead

Dismantling the machine really isn't the right option. 

If you're not going to buy new with delivery, you need a friend or two to help you carry it up the stairs. Completely do-able for two normal blokes.  The vast majority of people are happy to help out someone they barely/don't know. If you really don't have one or two friends or neighbours you're remotely friendly with then you need to hire one or two people to help you carry it up the stairs. Think task rabbit or similar. 

I'd suggest replacing the landlord's machine with the 'new' second hand one, and then selling the landlord's one to recover some of your money. You want the two machines swapped over, so get your helper(s) to help you bring the old one downstairs and the new one upstairs.

Yes, naughty to unilaterally swap the landlords property, but after all its something better, and they probably will never know.