So this is basically the bigger version of my house! It’s good you’ll have the garage for storage, will you be able to, for instance, use it store out of season clothes and bedding, children’s toys so you can have just one small box of them in house, and rotate them every few weeks? As well as obvious things like gardening gear, bicycles etc.
I would strongly suggest you have the small bedroom for yourself, you will really need some space to yourself. You could have a single bed (I mean, I’m short so don’t mind a single, you may be tall and need more space), and get a cabin bed, so can have room to keep all of your stuff in there with you? Then bunk beds and two children apiece in the other bedrooms. Little one could always be on a fold out bed with you sometimes to give older child a break, eg when one of them is ill?
This will sound daft, but have you ever watched the BBC programme; ‘Sort your life out with Stacy Solomon’? There’s three generations in my house, and we are very squashed in, and mad as it sounds I’ve found some really good tips on that programme that have helped me to make it work. We’ve been here a few years now, and I’ve finally managed to get into the position to have the loft converted, but tbh had to prioritise that as I have an autistic child who REALLY needs their own space now they are hitting puberty, without that issue I would have waited a few more years.
Buying and selling houses is so expensive, legal fees, stamp duty, and agency fees really add up! I would definitely stay put as long as possible once moved in, to avoid those fees and all of the disruption. Totally agree with you that buying makes more sense than renting though.
The main thing is to minimise the stuff you all have so there’s more room, you can always use curtains / screens etc to create privacy, but clutter is what makes the home feel too small. Alas I speak from experience 😂