Do it before you move *anything* into the house.

It's fairly hard work and very, very dusty.

You know how fit you are, whether you can lift the machine around etc
(30Kg-ish). If you have respiratory problems or significant back
problems, you might want to give it a miss.

Otherwise it's not particularly demanding on skill, but to get a high
standard of finish does require you to be meticulous - retract every
nail, secure anything that's loose, repair any damaged boards *before
you start sanding* and then get all the dust out before you start
varnishing.

One person can completely sand 2 rooms a day, including all the edging
- if you're less meticulous, and really go for it, maybe double that.