A chest freezer with temp controller is really a lot more practical than an upright fridge if you have the space. It's more efficient because cold air does pour out when you open the lid unlike a fridge door. You also have the option of a collar with taps through it, or a counter top and tower but it seems more people prefer the collar for practical purposes.
Go as big as you can afford / fit. I have a 14.8 cu ft which holds 8x 5 gal + 2x 3 gal on the compressor hump. I can also fit 2x half barrel sankeys if needed. Think that you can cold store / cold crash / lager etc in the same keggerator so add space for that too.
And buy Perlicks. They are more expensive than regular faucets but its worth it. If you save money and buy the cheaper rear seal taps, you WILL end up wanting to change them out, so do it right the first time.