You’ll pay more for hay than you have ever paid in your life. Buy in bulk or go in on a semi load with a few other people. We supplement with coastal. I’ve never had a problem with it…some people have.
Yes, you will lose shoes. Best to find a spot that is relatively high and dry, and have the horses in during the wettest times. And keratex helps.
Flysheets, flymasks, control your standing water, keep your pastures mowed, use fly predators - this will help with bugs and mosquitos.
Some horses stop sweating in the hot hot months, even the ones born here. I’ve had luck getting them to sweat again with 24 hours turnout with tree shade, access to tubs of water, lots of salt, one a-c, acupuncture, balanced minerals, and removing alfalfa from their diet. I don’t know why, but this seems to work and I just say a prayer and put them on the program when I see that they aren’t sweating well.
Learn to love your sunshirts and drink more water than you think you need. Carry a gallon jug.