I don't know how to decide.
House 1: a flat, but a big one. It has share of the freehold with it, as we insisted, plus a new 125yr lease.
Already had survey, needs about 5K work in terms of updating electrics and new boiler etc.
It has some minor issues with roof repair and replastering certain rooms but mainly is in nice condition.
Our offer is about 5k over what the surveyor suggested was fair, so we tried to renegotiate but they aren't having any of it.
Pros are it's in a really good street in a not-so-great town, ie the best bit of the area. Quiet road, Victorian house, biggish garden backing onto playing field. Posh neighbours! 
well some of them.
Cons are it's about half an hour drive from school, and from where we mostly will be shopping etc - I don't like the town it's in very much, but this part is nice. I think on the whole it's well placed for facilities once we move over properly (school/Dr etc)
Second house is already 12K + cheaper, and is in an old mining village which has a reputation as a bit sort of low key - not much there but a post office and a new development, there are a couple of not so nice streets but it has a small school and a church and there are a lot of families there - I know someone I like from school who lives there and she says it's fine. But it feels a bit council-estatey, a bit run down iyswim. Most of the houses are owned though and people have modernised them.
The one we're looking at hasn't been modernised - elderly person has clearly lived there and not done the whole knock-through, new kitchen thing, which is GREAT as it's a 30s house (all of them are the same age and similar design) and I like the original features.
It has a smaller garden but it has a large front garden too, and a garage and hard standing for car (the other one has on road parking which tends to be fairly easy but isn't guaranteed).
In terms of repairs it looks like it will need updating (elec and gas) but no more than the flat. Haven't had a survey on it obvs.
Space inside is around the same I think overall - maybe a bit more tricky to fit all our things in, but it's fine.
It's nearer to our town where we are now so that's better than the flat. But there's not much to do there. Mostly worried about potential for crime/disinterested youths/burglary etc.
Tempted by the fact it is a whole house though.
With my heart I love both...I could make both of them beautiful. So that's not much use as an indicator
How would you decide?