Manage your expectations re time it will take longer than you think
I hated hearing this but it will be worth it.
Dont skimp on correcting the floor insila re hear be careful not to block off vents that some older properties need. I’d join a specialist FB group an get advice.
In my experience trades/builders will often ‘advise’ whatever is easiest or within their competency. If you want wood have wood. Be patient and get it done how you want it or you will resent it every time you clean it etc.
Do it right do it once
I can’t emphasise the following enough- do not underestimate your capacity to learn how to do DIY stuff. It can take a lot of time but you can save loads of money:-
patch up walls - buy ready mixed stuff and a large ‘knife’ and filling in then sand - buy a mouse sander- loads cheaper and maybe ‘enough’ worst case is it’s a mess and you own a sander.
kitchen floor- if it’s a concrete floor tile or yourself or add those faux tiles
architrave and skirting - buy the right saw and you can get these done and save expensive daily joinery rates.
Focus on one area at a time - get one room done and nice take an break then do next
Its so much more satisfying too.