we were DIYing which is v different to having builders in I imagine, and we could limit it to one room at a time plus tools and paint pots all over the house
Kitchen fitting we found surprisingly fine. DH assembled the carcasses beforehand. We moved a few wall cupboards into the dining room, stood them on floor or dining table and used them to store pasta etc and basic crockery. Having a galley style kitchen helped as DH could treat each side as a separate project. We were hardly without a cooker, it was more that we didn't have time or space for complex meal prep or storing long lists of ingredients, so pasta, pizza and jacket pots were good and I don't think a slow cooker would have helped us that much.
The hardest thing is trying to work in the evenings and weekends when you're both tired from your day jobs and child wrangling. We tended to do one person took the kids and the other DIYed. Neither of you gets a rest. For some of it, I was on mat leave so having me do the work and DH look after the kids felt closer to a break than the other way round.
I agree with the PP, windows are quick and easy.
Having less stuff makes decamping from room to room easier, so I would seriously consider putting nonessentials into storage.
One of the toughest things with small children, we found, was going to DIY stores and making decisions, choosing fittings. I find child wrangling and decision making in shops practically impossible to do together. I've yet to find an answer to that one - you can't choose everything online. One particular tile shop won a particular place in my heart: it had a lego table...