I have a little experience in Florida and my advice is to not go cheap. Compare and get the lightest and most breathable for the money, and lighter is costlier. In the old days we wore level IIa, and thought II was too heavy to conceal. IIIa was for SWAT raid vests. Now the light and fancy stuff made of godknowswhatium is lighter in II than the old IIa. Depends on what the likely threat is, pistols or AP .30-06. The IIa stops most everything on the streets around here, YMMV.
Bottom line, if it's not comfortable, you won't wear it when you should. If you don't wear it, it won't protect you. If you knew you were going to need it, you would be better off not going there than stopping to put your vest on.
There are lots of good used, LEO surplus vests and such online with a bit of looking. Even Ebay has them.