You can do an entry level setup for under $600 if you know where to shop. Just for fun, I tried to see how close I could get to $500. Probably can't touch a dive computer though at that price. I'm doing this all thru LeisurePro.com since it's convenient. There may be better deals at some of the other on-line retailers on each piece also. Or better products on sale.
Regulators - either of these are entry level. They're also safe since they're flow-by designs - if the 1st stage fails, you'll still get air to surface. Both are known brands also with a long history behind them.
Cressi XS2/AC2 Piston Regulator at LeisurePro - $155.
or
Oceanic GT3 Sport (SP5) Piston Regulator, Black at LeisurePro - $170
A matching octo (same brand to make service easier at your dealer) is $60-63
Cressi XS Octopus at LeisurePro - $63
AERIS A1 Octopus, Yellow at LeisurePro - $60 Oceanic and Aeris are the same company.
If you can do the Hog Regs for around the same money, they might be better performers. They do have a much smaller dealer network for service though so be sure there's one near you - or you're willing to send them out. Scubatoys in Dallas is a HOG dealer. They also come in DIN/Yoke - you may want yoke for traveling, DIN if you can rent DIN tanks locally. Probably 90% of tanks you'll find at dive destinations are Yoke.
Then you need gauges -
Aeris Max-Depth Console at LeisurePro - $99
Now a BCD. The cheapest are $180. They're designed for rental fleets but in some ways that's better as they're bulletproof.
Of the two I like a few features on the Cressi better, 3 dump valves, seems like heavier duty material is used.
But the Sherwood was the more expensive initially.
Sherwood Silhouette BCD at LeisurePro - $180
Cressi Start BCD at LeisurePro - $180
For $10 more - I like this Tusa a little more - has a few extra features. Except the material used is lighter than the Cressi:
Tusa Charter BCD, Black (BCJ-2100) at LeisurePro - $190
So the way I would go is $530 plus any tax/shipping.
Oceanic GT-3 180
Aeris A1 - 60
Aeris Max Depth - 100
Tusa BJ-021 -190
So apparently it is possible to get a set of decent starter gear for around $500...who knew?
For $190-200 more you can add a cheap computer like the Mares Puck Wrist or the Aeris Manta. Functionally the difference is ease of use and probably the ability to log more dives without them being overwritten. And download capability. Almost all computers also have a "hidden" cost of almost $100 for their proprietary download cable also.
I also like the Hollis DG03 since it allows for future Air Integration reasonably. The computer is $250 and the transmitter is $250 more when you're ready. Hollis is the tech side of Oceanic/Aeris.
https://www.divegearexpress.com/computers/dg03.shtml
You might also try a similar exercise at Scubatoys.com Dive Right In Scuba, or Divers Supply. All are established online retailers.
If you find stuff you like, post it here somebody probably has used it.