Lived here nearly 20 years, house 22 years old.
Outside woodwork (window & door frames, conservatory, soffits, external doors etc). Pay someone to do them, done 4 times, last done 5 years ago and really need doing this year.
Internal window & door frames, skirting boards (all wood stain) - most of the house has been done once by me, although the spare room & utility were only this year. The main bathroom & ds2s room have never been done.
Lounge walls - soon after we moved in and again about 10 years ago when I had an extension, also did the extension. I washed them all down with sugar soap a couple of weeks ago when we moved the furniture to vax-wash the floors and it's made a real difference.
Hall, stairs & landing - all painted once, and reachable bits (so not right up into the stairwell) done again about 10 years ago in the same paint.
Kitchen & utility - once, last autumn during kitchen refit.
Conservatory - when new 17 years ago and a couple of times since including last autumn during kitchen refit. Gets marked from dogs and not much wall so easy to do.
Dining room & main bathroom - previous owners painted, I've not redone.
Spare bedroom & ds2s room - still original builders magnolia.
My bedroom - did a few years after moving in and have sugar soaped once.
Ds1s bedroom - did when pg in preparation, he is 18 shortly.
Re-painted some internal doors when the extension was done they looked really good, keep thinking I should do more but have never got round to it.
TBH while house (except kitchen, utility, conservatory) is looking tired and in need of a refresh, although sugar soaping does make a massive difference.