News flash houses need work, people need to stop thinking they are buying a band new perfect item, thats not how houses work. Owning a house and building a home requires effort and cost from you.
All old houses will have issue and most new builds are thrown up substandardly to be cash cows that are worse than old houses.
Apart from dog pee soaked floors that stuff is standard, not 'a dump'. You should always expect damp in a house its standard, damp doesn't equal 'bad'.
There is a huge difference between simple condensation damp (insulation and ventilation - which most building have to some degree) or white water leak damp (from roof/chimney etc... often easy fix) or a grey water leak (dripping u-bend etc... often hidden but easy small fix normally) or black/red flood water damp (serious, avoid like the plague usually. Although depending on cause could be salvageable with a FULL back to brick strip out).
You should also always budget for heating, even if everything is fine on exchange and completion it can break a day or week or month or 6 months into you living there through no fault of the previous owner.
Unless something is a recent full reno or has been a rental you should expect old wiring too, its pretty normal in long lived in homes.
You should budget for these obvious basic maintenance fixes in you housing budget. Almost all houses have them so its actually better to know upfront what bits need fixing rather than the surprise of it being hidden.
Its weird people look top end of budget or above budget and don't expect standard little issues they need to fix.