I'm annoyed with myself for even posting this in a way because I shouldn't need to ask. I know plenty of parents who seem to give their children wonderful childhoods, despite not having much money and living in small flats or houses. I also know from personal experience that growing up in a big house with a big garden is zero guarantee of turning into a confident and mentally well-adjusted individual! (although the garden was very fun).
DH, toddler DD, DDog and I live in a small 2-bedroomed terraced house with a little grassy garden. We like it. We are also mortgage-free.
We've thought about moving somewhere bigger because we both got promoted at work recently and suddenly find we are in the incredible position of having a lot of spare income. Our own house wouldn't sell for much (possibly not much over £110,000) but we could upsize a lot without too much pain.
On the other hand... we're settled here. We like the area. We have enough room to entertain the local family and friends who we care about. We could put some of the extra money into upgrading our house and making it nicer, and have a lot to spare.
Ok, DD will never be able to have a double bed, an en suite or a big trampoline and climbing frame, but does she really need these things? Wouldn't she rather have a good university fund / house ladder fund for the future, and the chance to have lots of cool holidays and experiences? Parents who can afford to cut down our working hours a bit soon so that one of us can be fully present with her after school each day? Plus there are lots of lovely play parks nearby and we go a lot.
I have a few friends and family members who reckon DD will be embarrassed by our house one day and will want more space. They act like I'm depriving my DD of a better future by staying put. I also suspect they look down on where I live. (Quote from one: 'I couldn't live like that'.)
Equally, I very much hope not to raise an entitled brat who judges value by house size, and I don't like the idea of buying into a sort of competitive house-upgrading culture now just because I can when I've never been interested before when I couldn't.
We have a sofa bed in the lounge for guests and I don't get why a family of 3 people need a bunch of spare rooms.
YABU - get a bigger house
YANBU - stay put