hello, i jumped into the deep end first. 220g also lol
a few beginner tips for you that i went through. location is just as important as what you're getting.
As a tannk filled with water will weigh a lot. so if you want it on the second floor its best to ask a contractor if the floor will hold the weight . As mention above convenience will be a factor for water changes. ideally you want find a wall on the first floor with no direct sunlight. If it is going to be in front of a window be sure to cover up well.
whether you're going for a reef of fowlr, a saltwater set up demands a lot of attention, good husbandry and a lot of research. Cost is another factor. in this hobby you get what you pay for. there are cheaper alternatives then the grade A items, but even then you are looking to shell out a pretty penny for a setup. join a local reef forum and check out the used section. more often then so you will good deals with people upgrading and such, you find yourself a whole setup for like $600
I'm a believer of getting as big as you can afford. setting up a fish tank isn't really an impulse thing, usually people lose that "impulse" when they start looking at cost. Its not something you can buy today and have it setup by the evening.
Youtube is gonna be your best friend, so many videos, explanations and how to's make the learning curve of this hobby survivable. i got so confused when i was learning (and still learning). if you get a smaller tank, theirs going to be a high chance you're going to want to upgrade pretty soon. then you have the headache of moving livestock selling old equipment that isnt big enough for the new tank etc etc. the absolute smallest i would go is a 40g. large enough to look good and give you some headway if things go south but small enough that the cost wont cripple you. with so many used tank around a 90g setup soon becomes somewhat affordable. if you havent already check out the BRS series 52 weeks of reefing. very educational and helped me alot.
As mentioned above, stock will likely dictate what size tank you start out with. with me, i like fish. So we opted for a large 220g. My son likes corals. so now i have a 220 going for a mix reef. aside from stock choices, when people say a larger tank is easier. Its because with a larger water volume you have more dilution when and if things go south. a fish dying that you didnt know about will effect a smaller 40g faster then a 200g. giving you more time to see and take action. this is the same for keeping water parameters. fluctuations arint nearly as steep with a larger tank. downside being, you need bigger equipment.
Being efficient in DIY will help you save a few dollars when it comes to things like stands, plumbing, lighting (i made hanging light box with 2x4 and a canoe harness to house a hybrid kessil/T5) and tank outfitting (i drilled my own holes and made my own overflow box)
i think the last and probably the best advice i can give is; don't be afraid to ask questions. no question is stupid or noobish.