Short answer - it is not for everyone and you will make lots of compromises along the way. It is not cheap, it is not comfortable and it is not spacious. If you think house repairs are expensive, then you are in for a major shock and don't get me started on the plumbing situation! Right, now that is off my chest, a bit more nuanced advice
Background - I work about 100 miles from home, but pretty much 200 meters from work is a marina. No brainer think I after yet another miserable commute, buy a boat and relax after work instead of commuting. So for 2 years I spent 2 or 3 nights a week on a boat. It was a 1970's fibre glass broads cruiser, 32ft long, 10ft wide, 4 berth. 2 toilets, one into a holding tank and one direct into the river (that I couldn't use in a marina so dead space). Small galley kitchen but fine for me, shower I couldn't stand up in and sofa's that were not remotely comfortable.
Pro's - convenience. This is nothing to do with living on a boat so much as removing larger hassles from my life for a while. The thing I enjoyed most, bizarrely, was lying in bed and the boat rocking gently on the water, and being snug in the boat when it was raining heavily outside. Just something about the noise of the rain on the roof that is impossible to get in a house.
Con's - expense. It costs to insure, to have a safety certificate, to moor, to empty the poop tank, to have shore power, to repair, to run, the list seemed to be endless. Admittedly it was an older boat but even so, it cost far more than I was expecting. Damp. Boats leak. If you cannot see a leak, it is leaking somewhere you cannot yet see - the bilge pump is there for a reason, make sure it works! Boats leak through seals, through windows, hatches, cracks, via osmosis and in seemingly inexplicable places no matter what you try. Temperature. A boat is like a car left outside - icy in the winter, horrendously hot in the Summer. I used to run an oil fired rad on low all night in the bedroom when I was on the boat, but when I was not there damp and cold is a major problem (closely followed by mould). Comfort. Everything on a boat is a compromise - where does your washing machine drain to in a marina? Got space for a tumble dryer? You wont have a free standing sofa from dfs, more likely a hard seat with a cushion on it. Want an electric cooker? Don't expect to just pick one up from AO.com, lots of rules and regs around appliances on a boat. Power. Shore power is fine when it works, but it is on a meter and needs topping up. Not sure what your rating is at the main switch but check you can run enough appliances simultaneously. Location. Where in the marina are you - near the shower block or tucked away on the edge. Fine to walk to on a Summers afternoon, try 2am in December when the pontoons are iced over and frozen. Space. Even a widebeam is going to be cramped for a family compared to a house. Think about living in a large caravan - a boat is more cramped than this. No garden, limited privacy. Drainage. If you have a mobile pump to empty your poop tanks then great, but if not, manouvering your boat if a widebeam is a major hassle. There are other con's but that is probably enough to be getting along with.
I don't know your situation, but a couple of things I would recommend - try a holiday on one and see how you get on. Imagine while you are doing it that this is a way of life, not a bit of fun for a week or two. Then think about the logistics - getting 'stuff' to and from the boat is a pain, from a weekly shop to directions for an amazon delivery. Try to talk to people that are in the marina - boaters are a friendly lot in the main and I have found many of them to be overly helpful on occasion. The ones you really want are the ones who live aboard, but they can be a bit evangelical about the lifestyle if not careful - a bit like caravan owners. It takes a certain mindset to put up with the hassles.
I wouldn't say don't do it, but it is not simply a 'house alternative' that saves you a fortune, so you are doing the right thing by asking advice first. I did likewise but still was not prepared for the sheer inconvenience of the lifestyle. I stuck it for 2 years and sold just as the pandemic started. If I had had a newer boat then it may have been more bearable in terms of comfort and damp, but space would always be an issue for me as well as the high expense of upkeep. I was keeping a house and a boat at the same time though, so if you only have a boat to worry about this may not be such a factor.
Best of luck if you do decide to go for it!