My initial thought is to write it as an addendum with specifics of how many weeks a year, max duration, rent will be prorated that month, dates must be agreed upon with tenant at least 3 months in advance, etc Thoughts?

I have email auto-responders that provide info and links to our website, walk-thru videos and a short application form when someone makes an initial inquiry. 

This creates two loan payments ($100,000 of equity and $300,000 on the new mortgage).Key NumbersHome Equity Loan Interest Rate: 6%Mortgage Interest Rate: 7%Rental Income: $3,000 per monthExpenses (management, taxes, insurance, maintenance): $800 per monthIncome and ExpensesMonthly Rental Income: $3,000Monthly Expenses: $800Monthly Mortgage Payment: $2,000ExplanationThe investor earns $3,000 in rent each month.They pay $2,000 on the investment property mortgage and $800 on other expenses.This leaves $200 profit each month or $2,400 per year.However, you have to pay $6,000 interest on the equity borrowed.This leaves you with an annual loss of $3,600.This example shows that while the rental property generates positive monthly income, the interest cost of borrowing the initial $100,000 results in an overall annual loss.

Remedy after termination.If the rental agreement is terminated, the landlord may have a claim for possession and for rent and a separate claim for actual damages for breach of the rental agreement, reasonable attorney fees as provided in § 55.1-1245, and the cost of service of any notice under § 55.1-1245 or 55.1-1415 or process by a sheriff or private process server, which cost shall not exceed the amount authorized by § 55.1-1247, and such claims may be enforced, without limitation, by initiating an action for unlawful entry or detainer.

Initially, covering your mortgage is a reasonable goal.

Don't hesitate to go slow initially, learn from the first few deals, and pick up the pace once you've locked in your process.Good luck!

Feel free to reach out if you have any projects or initiatives in mind. 

Document the change in your policy and be clear about the new criteria in your advertising or initial responses to interested renters.

I had initially gotten the property with personal funds plus a hard money loan.

I initially planned on doing month to month lease for incoming tenants just in case I need to let them go if they end up not being the right fit.