Questions/worries about turnkey rental props

[Shari Posey]

I've been thinking about turnkey properties and one thought keeps popping up in my mind and I wonder if it's valid...since these props come with a tenant already installed, have some made a side deal with the tenants to slide some money under the table and beef up the rents for the length of the lease? Obviously I will have to do my own due diligence on rental prices but some that I've seen seem higher than market, which is what makes me wonder.

Also, how long are you locked into their property management system typically? Some of the management fees seem on the high side as well.