I don’t know, I think some folks are asking the op to spend a lot. I think she needs to set a budget and work out how much to sell it for.
Not everyone has the kind of money to throw at things being suggested here, I’d not replace all the doors, that’s really expensive, I’d potentially paint them, but that’s all I’d do. I think some folks have oodles of cash to spare.
I’d defo clean all the carpets, and the walls, and power wash outside . Front and back,
There’s some money in the ceiling repairs to be spent. I’d consider replacing the green carpet depending on budget available, if not a good professional clean,
I’d then buy some white paint and some polyfilla and paint the top floor and the shower there.
Honestly I’m not sure I’d go further than that. I’d put some nice pots she can take with her outside at the front, and tidy up the back.
Honestly I don’t think I’d do more than that.