@Clifford C Toth No, I don't rent them furnished, although in my market you can get an extra $50/BR for doing so.I have a 3rd party do the lawn 2x/month.

Now out of that small percentage, there's an even smaller percentage where the extra 1/10th of a second you get by carrying open makes a difference.

I am working on what to fill the extra time with at the moment.  

It works great for wholesalers who sell the deals to a flipper, so a flipper can reap the rewards by going the extra mile and conducting their own marketing

Maybe take extra steps like walking the prospect to their car and glancing into it, while that is not a 100% indication that they will be a good resident, it definitely helps.

Consider remote monitoring tools (like security cameras), and budget an extra 10-15% for surprises.

Keeping this as a rental would not cover the mortgage (we'd have to pay ~1500 a month including utilities) and we can afford the extra payment, but is it worth it when looking at appreciation?

I suggest going the extra mile by providing access to these services yourself, and you could even advertise features like $5 movie rentals on Prime Video to create additional value for your guests.Hope that helps, and good luck with your investment in Cancun!

I know the addage if you treat it like a hobby it will pay you like a hobby but if I have some extra cash maybe it's better spent on a 2nd home with the potential for income vs. just using that money in my primary home. 

That is basically an extra tax return, legal fees for setup, bookkeeping costs (if you aren't doing it yourself), possibly an umbrella policy.