@Matt Geerts I believe someone can register an instrument against your property, for any amount, with your consent.

However, depends on area (ie Cali age of consent is 18 so soon as one part of a couple turns 18 the other is breaking the law).

Sample wording: PETS: No pets will be brought or kept on the premises without prior written consent of the LANDLORD in the form of an addendum to this contract.

The writer said he'd "consent" to a phone call with me.

RCW 59.18.150(1) The tenant shall not unreasonably withhold consent to the landlord to enter into the dwelling unit in order to... exhibit the dwelling unit to prospective or actual purchasers...(5) ...The tenant shall not unreasonably withhold consent to the landlord to enter the dwelling unit at a specified time where the landlord has given at least one day's notice of intent to enter to exhibit the dwelling unit to prospective or actual purchasers or tenants.

Doesn't mean there isn't a law preventing that business transaction consisting of two happy and consenting adults. 

In South Carolina, is consent for background checks required?

@ChrisI think there could be a market for this, but...wouldn't the tenant have to sign a consent form for someone to do this monitoring?

Be aware, do not give the family access to the house without the consent of the tenant or his legal representative.

CODE:(1) the term “due-on-sale clause” means a contract provision which authorizes a lender, AT ITS OPTION, to declare due and payable sums secured by the lender’s security instrument if all or any part of the property, or an interest therein, securing the real property loan is sold or transferred without the lender’s prior written consent; Please note: "AT ITS OPTION"I've been all the way (took 5 years and $125,000 in legal fees) to the Ninth Circuit on this very issue and Won.