On occasion, they have required coverage of 200 to 300% of market price. 

If it comes down to it she can always pay an escrow company to distribute the funds each month - so you know the money is coming, but you're not the one holding the cash until the service (tenancy) is rendered.If she's in the middle of a divorce she may be able to have her legal counsel distribute funds.I see these threads on occasion and this is the best advice I've ever seen to solve the issue.

I've seen occasions where the lease had to be bought out when the property transfers which ended up killing some deals.

I don't want to get shot... walking into a home that is occupied without announcing your self is very dangerous for the Agent.Not sure how the other agents who answered on this thread do it.. but thats what I do on the rare occasions I am actually walking into someones home.

If your lease is anything like my rental lease it says that the tenant is responsible for YOUR legal fees and court costs so you should be bringing a court action against them for non-payment of rent and they would be responsible for your back rent AND your attorney costs.Dealing with attorneys gets expensive but it is a necessary evil on occasion.

She has also been a guest speaker at my local Real Estate investment group on several occasions.

It's where I've found my tenants on occasion.

One tenant refused access on 1 occasion and the key was missing on the second try (likely a realtor trying to make sure there was less competition), but we made an offer based on the other two units.Some areas have mandatory rental inspections, so I would check to make sure the property is current.  

The house is the home of your tenant, and your tenant has rights, like having visitors coming to stay on occasion, and there is not a single thing you can and do about it.

I have uncovered fraud in doing this work and have cooperated with authorities on more than one occasion.