(Max vacated rents - your monthly mortgage payment) = +/- net cashflow.

Currently, we own one vacation rental in Duluth and one college rental. 

Sellers may struggle to mentally shift from "owner" to "tenant," which can create challenges with boundaries and property care.Security Deposit:If you’re doing a temporary leaseback, be sure to collect a substantial security deposit to cover potential damages and ensure they vacate on time.

My wife and I spend a lot of time together, we take vacations regularly, and I prioritize my health by working out 3–4 days a week and getting 7–8 hours of sleep most nights.

I would like to buy a future retirement home to get away from the cold winters but in the meantime would love to rent it out as a vacation rental.What are the good areas to consider and where would I get the most vacation renters and cash flow?

If you can hold on until the end of lease term, you can give a written notice and also send an email which would be Notice to Vacate. 

Borrow against it as needed for retirement and keep it as a high end rental if they want to vacate it.  

I need to reach people looking for temporary housing, but not vacationers - because Castle Rock is not a place people go for extended vacations, especially in winter.

You can build a Vacation home down there and put less money down and still rent it out and later just transition it into a full time rental!

This is true regardless of how long you have owned a vacation rental.