The plan is to out down 5%, live in the house, and rent out out our current house (this would be our 2nd property).The comps don't justify the price, but the upgrades and current market climate do.

I have been in North Texas in the Dallas area for over 20 years and witnessed tremendous growth,  There has been an ongoing trend where the southern states have an advantage from many perspectives (cost of living and affordability, more favorable taxes, climate, etc).  

The two main differences I can envision for Kevin would be: first, he's in FL so there may be specific building requirements for FL, vs. here (no doubt there are, as its a completely different climate and hence building requirements). 

Has anyone here decided against buying something because concern about long term climate change (specifically rising sea levels and increased flooding)?

But I think as a backup plan you always have nurses and other health care professionals with St Anthony's, Bayfront, All Children's, not to mention the people moving here from colder climates, that you should be able to just swap to a furnished monthly rental and do ok. 

Climate control systemsInterior and exterior lightsSignageSecurity and access control systemsOffice and maintenance equipmentPaved surfaces and walkwaysElevators and material handling equipmentShelving and storage systemsIf you have a self-storage property, have you utilized a cost segregation study?

Swap coolers are not the best.... water leaking, only work when its cooler- not geared for the climate changes and hotter summers we are seeing. 

However, I have heard they are costly to install and can be troublesome in a New England climate.

Whatever you do, just don’t go with the mechanical deadbolt varieties in climates with high temperature variability.

I think your analysis about keeping it as a LTR is the best option. 3 months is a rather long time in this current climate of continued interest rate hikes, coupled with downward pressure on sale prices.