If they cannot be present, they must designate an adult (18 or older) representative to be present on their behalf. 

So they had to move in with relatives.  4 adults, 3 'kids' (of the relative) 16, 17 and 19 yo in a small, less than 1000 sq ft, 3 bedroom house. 

Provide proper care for the pet in accordance with veterinary recommendations or ASPCA (American Society for the Prevention of Cruelty to Animals) guidelines.

How many working adults?

Can an adult just co-sign contracts for me or can their name be on the contract and they sign and I just say that they are my partner, I have also read that a contact is legally binding if the adult guardian of the minor gives permission to the minor to enter the contract?

RyanAnother company that may be able to help is American Modern Home.  

Every adult that will reside in the rental must be screened.

I neither like nor understand the American practice of tipping people for doing their jobs or just for doing things they wanted to do, but certainly it is widespread.

It's very hard to fit an adult size bed in any of the rooms.

We are a bit unique in that we have spent the last decade operating some of the largest REITs in the country (Waypoint/Invitation Homes, Progress Residential, American Homes 4 Rent, etc.) and take more of an asset management approach with our investors.