I dive south florida, for protection i have 3 setups Boardshorts/tshirt, 3mm Shorty wetsuit $40, and 3mm Full wetsuit $80. Fins can run you anywhere from 30-250ish mine are like 150 but i got them for $45 from Gander mountains supercloseout on scuba gear, A bc is about 200-1000 Mine was from a friend for like $50 bucks but its really faded and ugly, A reg is about 200 up, you should be looking in about the 350ish up range though (mine was a demo model from LDS so paid 245 which is alittle over half price) you could start with analog gauges then switch depth out with a puck on some consoles that would start you at about 100, then a comp would be about 300 or you could just get something like the oceanic veo for about 350 or a geko for like 300ish.
with a reg make try to get one that is balanced and avoid used because you should get them serviced every year and not knowing the maintnance, service is highly recommended and runs about 60-100. That makes most used regs cost almost the same as new.
Asfar as BC's the only things to go bad are the actual material which visually looking over it you will have an idea, The Bladder which some are replaceable (Zeagle's usually are) the dump valves which are a few bucks and the Power inflator which you can get for about $30. You can check most of that stuff by looking it over, hook the BC to a tank let it sit at first and see if it inflates on its own then fill it up and see if it drains on its own if it doesnt fill/ drain on its own it should be good
If your just doing basic diving and are responsible enough and smart enough to use analog, financially its the way to go, Computers are a convenience/safety item that help ALOT with safety and turn around reminders, kinda maximize your bottom time and for learning your dive profile to learn about your dive if you get a comp (which is highly recommended) make sure its nitrox compatible because cost isnt much different and you may move into nitrox
if you shop around well depending on temp of waters i would say your looking at about 800 for a good setup that is overkill but to the extent you will grow into it +thermo protection. Smartest thing would be to look at the diving you will be doing over the next year or 2 and how much then invest the money that fits accordingly with it, if your diving occasionally through the next 2 years and only 60' or less then a $400ish rig should work, but if you plan to dive more often and deeper i would start by switching to a better reg then computer. If you buy everything from the same shop they may discount some of the stuff since your droping a few bucks in their shop too
Im fortunate that I found a sports authority mask sealed well on me, and i got my fins for REALLY cheap, my snorkle setup was just about $100, and my entire dive setup was about 900, but i could have gotten away with about 500 just because i went way overkill on the computer with hoseless air itegrated
