There are a bunch of ways to do this depending on the property type, usage, and you (income and credit scores).If this is a primary residence, you can get up to 90% of the value of your home minus any exisitng debt. 

This is because they're much more expensive than other countries in the region and, unlike in some other countries in the region Costa Rica doesn't have the mass tourism needed to get you the rental income that would justify those prices.This being said, it shouldn't be hard for you to break even though since all you'd need to do for that is cover your costs.

It doesn't matter what your rental income is.Anyone could buy in your neighborhood and make a STR.

If the current rents are below market, maybe it’s time for some modest increases, from what I’ve heard many landlords do this gradually.

And assets that provide you with great depreciation but not great income or stability are just a form of robbing from Peter to pay Paul.   

STRs generally produce more income than LTRs, but they are more work.

Real estate's "gross rent multiplier" is Wall Street's "sales to revenue",  "cap rate" is roughly "P/E ratio".When evaluating markets and investments I tend to start with GRM (or lazily the 1% rule), then attempt to return a cap rate based on assumptions about costs, then I work my way to multiple years of projections (assumptions about inflation, amortization, tax benefits, etc), and if I am partnering with one of my smart friends I have to pull up an IRR (internal rate of return).I also look at regional employment levels, median income to rent ratio in the zip code etc. 

I’m not looking to retire early or replace my income through rentals—I just want to diversify our assets.

It has limited new construction, low property taxes, and no state income tax.

Income vs Capital Gain.