Well, this (in bold) says it all. In my mind, if you really don't want to be a landlord, regardless the reason, then that should be the bottom line. Happy wife, happy life! Don't ask how I know...
I get that he wants to escape to FL for the winter, and it can be a challenge to find something decent during prime time. Friends spend $4K/month renting a house for 3-4 months near the Gulf. He had to agree to 4 months to lot in a lease; seems like a seller's market during peak season. Maybe it would be easier and cheaper to find just a small condo.
Has your husband wintered in FL much?? I agree with the suggestions to rent and/or live with his brother a few times before even thinking about buying a place. Local knowledge is precious.
We just got back from SE Arizona. Wondered if it would be nice to eventually relocate to escape the northern winters. Well, the places that we would even consider buying cost more there (say Tucson) than they would in our overpriced midwestern metro area. After spending a month down there, we would certainly visit again, but less inclined to stay several months, let along buy a place. Dreams are often most vivid from far away....
Last year, we were dreaming of coastal TX. Got to know some of the friendly locals too during a few weeks weeks of snow birding. Were thinking, maybe "we would do this". After the 2017 hurricane, we're thankful it was only a passing fancy...