All depends on how much you are likely to squat really, how much you want to spend, and if these are going to be your main workouts, or maybe just to fill in on days you can't get to the gym.
If you are insisting on free bar back squats the kit needn't be TOO bulky, You can get these cheap squat stands on eBay that stack together when not it use for £35 -https://www.ebay.co.uk/itm/2X-Adjustable-Gym-dumbbell-Squat-Barbell-Stand-Rack-Press-Weight-Bench-41-To-66/143002124109?epid=5024254289&hash=item214b973f4d:g:e2UAAOSwoZlb4Fxm:rk:7:pf:0
Bars .... Unless you have a really good amount of space width wise , then I'd opt for a 6ft one rather than a 7ft, Shouldn't be much more than £40 if you shop around.
And then weights... if you can load up with 15kgs, then these represent the best lb for £ I have seen, (and I have searched pretty well) You'll pay £33 per 30kg. There is usually a 5% code that takes this down to £31 or so. If you can use these as your "bulk" plates, you'll just need some increment plates.
But like I said, it depends on how much you need to lift really, and how much you want to spend, the above set up is all "proper" gear that should last forever.
.... all that said, I can't help thinking Split sqauts (or whatever they call them this week?) are made for this situation, very little equipment required here, and not as much weight at all. but take a bit of learning to get them right and effective. All you need is something to elevate your resting leg, and some resistance, dumbbells or whatever, possibly even bands?
By far the neatest solution has to be bands though, I am loving playing around with my set up, and how I can use bands to replace, or work with my equipment for some exercises, this guy has some great videos.
If you can make these band exercises work for you, then you won't beat this solution for convenience, no noise, no floor stress, can virtually fit in your pocket! Cheap too.