I would not focus so much on the returns, as I would on the experience of the sponsor and team, location of the property, and overall business plan. 

What is the plan if it doesn't work?

I use Follow Up Boss and just have each lead tagged differently with different action plans

My husband and I are planning on putting one the rooms in our house on airbnb, either as a short term or medium term rental for travel Healthcare workers and such.

I'm in the process of getting a landlord insurance policy quote.

Did you talk to any of the tenants while you were under contract to go over the plan?

@Ray WhiteI recommend finding an accountant who specializes in real estate taxation and tax planning for high earners.

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.

That sounds like a well-considered plan, and visiting in person is a great first step.

Very well qualified borrowers can often obtain favorable terms from their existing banking relationship and sometimes even borrow against non-real estate related capital assets such as money market, life insurance or investment accounts.