Possible to do a staged bathroom reno?

We recently bought a property with some issues under the bathroom - basically a cheapo reno was done some time back and it appears water has been leaking through the back wall and has rotted out part of the wall and the joists behind and under the tub.

The bathroom is 80s with asbestos water proof sheeting which is blistering and the bath is very, very grotty.

I want to get rid of the whole lot, but I'm not sure we can afford a complete gut job on top of the issues of fixing up the subfloor.

We are happy to do as much of the ripping out/labour side of it as we can, but we're not handy with tiling or anything like that.

Do you think it could be possible to do it in stages? What bits need to be done first? Advice generally?

Thanks

Generally
1 Do not interfere with asbestos
2 Renovations could mean broken asbestos under home
3 Get rid of leaks and ventilate well to dry up
4 Check for termites

Only then you can move forward