Welcome Ron:
Also being in Florida I can help you with most matters, but the major decisions are yours
1- That's the hardest one to answer. It depends on the grade selected.
2- No
3- Yes. Reasons being the lack of qualified individuals doing site finished floors. Engineered hardwoods will provide more stability, but having the right professional doing the job with attention to what causes failures is the advantage in any job.
4- Good quality square edge prefinished products are hard to come by. What many don't realize when making a decision is what kind of overwood to expect. IE- differences in overall vertical height from one board to another after installation.
5- Depends on care and what you deem "needs refinishing"
6- Too many variables--maybe others can help
7- With solid 3/4" products yes--engineered no.
8- Biased opinion--no answer