1. Buy only in areas you know well, preferably close to where you live now. Not only are you more likely to get a great deal because of your knowledge, but you'll be nearby when management issues arise -- even if you have a management company. (I bought my first investment property last year 800 miles away, but in the area where I grew up.)
2. Since you live in Florida, you know the two biggest expenses, higher than in most parts of the country, are property tax (because we have no state income tax), and insurance (since we have hurricanes every decade or so, and even though most parts of Florida have not been hit by a hurricane in forever, as opposed to much of the NE, we still pay outrageous homeowners insurance). So be sure to factor in those two big expenses when considering a rental/investment property.
3. No Realtor is ever going to be as knowledgeable as you are. Seriously. Sure, they might live in the area and been selling homes there forever, but they just want to make a sale and they're not going to look at it objectively as a business. I got my real estate license 14 years ago, not because I ever wanted to sell real estate (and I haven't), but because I was so frustrated by idiot Realtors, I wanted to understand the process better. Even when I finally bought a second home/vacation rental/investment property last year, it was from a Realtor I like a lot, but a guy who hated the property and didn't want to show it to me. He has since admitted I got the best value in the area in the last decade.