Once the lease expires, provide notice to vacate to both parties and move on from them.  

Adding a second (or maybe third) living space can add value to most vacation rentals.

If I mainly want to vacation in Costa Rica and stay in a nice place, I rather make more money by investing elsewhere and rent a different villa every year, which is much more exciting from a lifestyle point of view, as I'll have variety.

One is 100% cash flow, one makes some cash, and the third is about $13000-$15000 (management fees only, mortgage and escrow are covered) per year short of breaking even—we understand that this vacation rental was an investment and are content to wait another year or so before it provides a cash flow.

But first the backstory….My father immigrated to this country over 30 years ago and has been able to acquire 4 properties in that span. 1 family home in long island, two 2 family homes in Queens and 1 vacation home in his country.

Like you said it gives the weekend for travel time.Plus, if folks need to head home on Sunday then they do that and not feel too bad about losing a day.When you have to work that Friday, it sucks because you want to get started, but after 6 days of vacationing, people are often ready to go home and are meh about the Monday.Psychological Strategery....

I don't have a judgementDo you have to hire a lawyer if the tenant has already Vacated? 

You can still find some great cottage style homes or even 2-4 units close to the beach that have great STR returns.One good thing about being out of state in IL is you can find a good Single family home, Condo, or Townhome and call it a Vacation home and only need 10% down. 

I assume that  if you knock on the door they are not going to be receptive to your request to vacate.

Hey @Michael Baum what about buying a couple snowmobiles, making an ice rink, buy some snow shoes , fireplace …voilà the ultimate winter vacation spot for your “Offseason “(snowmobile  is expensive I know )