Thank you so much everyone. We're viewing number 3 this afternoon, viewed the other two (and walked around the areas extensively). Budget is £350k at the outside but I'd very much like to be under this so we don't resent paying our mortgage if rates rise even more than they have. My heart says number 3 but it's a bit out of town and DC1 would need to change school (he starts in September and IDK if there will be spaces so soon after the big allocations process), I can just really see the little ones playing in that garden (especially if we rip that shed out and let it go a bit wild, perfect for little explorers).
House 1 has an additional £14k of auction costs that neither me nor the seller will see, but which also adds onto the stamp duty liability, which pushes it up to £364k, so with that and the added money for refurbishment, it would be a seriously hard stretch to afford to do the work and would probably take us years to sort it properly due to needing to save up. With house 1 having no upstairs bathroom, it's going to lose the third bedroom to move the bathroom upstairs, so that doesn't give us three rooms anyway. I am 99% sure the square footage includes the condemned conservatory that needs demolishing.
Thoughts on house 2 are that the garden is bigger than a flat balcony, and big enough to put a playhouse in. We could rip out the silly ensuite and move the wall a bit to turn it into a small third bedroom. However, while we were viewing it, some idiot in a Range Rover came and double parked over the back of our "allocated parking" in our second parking spot (which is behind the first one), blocking the owners in. I feel like with it backing onto a small car park it's going to be constant parking drama, which massively puts me off.
House 3 has that little garden room off the kitchen which we thought could be turned into a temporary bedroom if needed until we could afford to upsize to something bigger.
@Cherrycola29k honestly after viewing house 1, DH and me felt exactly the same way even though logically it does seem by far the best investment. The pictures don't convey the smell at all.
Maybe we need to sit it out until something better comes up.