I find the cap rates for these to be very compressed on the West coast.. and can be very high out in the mid west deep south..

Less red tape & quicker closings but typically the rates and lender fees are higher.

My team and I dive deep into market analytics to provide our clients with comprehensive reports that guide them in making informed, data-driven choices when entering new markets and setting up their vacation rentals.Moreover, we prioritize a human-centric approach in our designs, ensuring that not only are the aesthetics on point, but the functionality and comfort lead to happy guests and consistently stellar reviews.

Without knowing more details about the specifics of the project being proposed as it relates to your property, it's hard to say if there are any obvious big red flags that could negatively impact your property's future value.That being said, I would try to find out as much information as possible about the new apartment building's design and layout - the two big things I would try to ascertain would be the location of the garage entrances/exits, as well as the location of any outdoor amenity spaces (pools, terraces, dog runs, etc).  

I've been deep-diving this thought process for days haha

In this day and age, not having a online Prescence and clearly documented track record is just a huge red flag

even suburban submarkets are red hot right now in miami like leisure city, homestead, florida city you can still get infill lots one of the last few places in miami dade county right now. rezoning and variances you can do even better. if you are limited on capital ground up construction and land might be something to consider in miami in these submarkets.

That’s what I see  So thats the contradiction is that. and thats the red flag for me....they live a debt free life but have a car payment.

What red flags should I look for that would lead me to see a property that has been sitting as an “unwise” investment

If they are not, that's a red flag.