Understand the fees involved and calculate the total cost for an entire year of management so you can compare the different managers.

For a conventional loan, you can borrow UP to what you paid for the property plus closing costs OR 75% of the appraised value which ever is less.  

The biggest factors, from what I can tell, are age and rebuild cost. 

This will be costly in today's market and interest rates, but might be worth a shot if they can afford to stay.If they don't want to stay and you want the the townhome to rent to someone else and just want to assume the loan, well then she can call the lender and see if the loan is assumable. 

Usually you can negotiate it for a few thousand and buying new costs about $20/ft. 

Are there risks or hidden costs I might not be considering?

Real numbers- purchase 907k,rehab , closing costs, soft costs, 840k, all in 1.747 mil, basis for each unit should be roughly 291kappraisal of each unit minimum 400k , so 2.4 mil if for all 6.I might refi only 4 out of 6, that will cover initial loan amount.

Just a cost of doing business.

Assuming your property is in Utah (like your profile indicates), here's the state law from a basic internet search:In Utah, a tenant who abandons a rental property without notice is liable for the lesser of the following: The rent remaining on the leaseThe rent plus the difference between the fair rental value and the agreed-upon rentThe cost to restore the property to its original conditionThe landlord can also remove the tenant's belongings and sell them if the tenant doesn't claim them within a reasonable time.

Houfy now has a damage protection plan that costs the guests $5 a night and does light identity screening through SuperHog.