I lucked out and got a large fridge freezer sized larder fridge a mate was throwing out and its been ace, but before that was doing fine with under counter larger fridges for fermenting. My brewzilla fitted in fine but needed a blow off instead of an air lock as I had to raise the fermzilla onto the hump. that left a space underneath for a tube heater.
Beware as not all larder fridges are the same size and I did buy one locally for about £20 but was a bit smaller than what I considered to be a standard 600mm under counter fridge.
It works perfectly fine as a solution and can maintain fermentation temps more than adequately enough and doing this was the single biggest improvement for my results than anything...it literally lifted my beers to the next level in one step, though there are always many more levels to climb, so I would recommend to anyone just do it if you can. Ahead of anything else...it is the single most important and impactful upgrade you can make to your brewing process.