The agent is pressuring me to get contractor estimates. 

However, I have made two contractors change.

What some of the banks have told me is if you can provide a quote from your contractor and proof that the work was completed that they would take that into consideration. 

If dealing with a contractor who will refuse to provide you with free and accurate cost estimates then you have to add that costs on your end in order to even work a deal out as a  wholesaler. 

If you have an investor that is looking for something specific and you have found it but it's listed with a realtor who would sign the assignment contract or is one not needed?

However, not sure if hiring a contractor would be cheaper than buying a premanufactured guest house?

I'm interviewing contractors: any suggestions based on personal experience?

Overall the house has great bones but it will take a few grand to complete the punch list of items needed to remedy: radon mitigation, surface mold in attic, slight leaks at a few easily accessible spots in the roof, electrical service work.

I stick with the easy things, and hopefully not time consuming..Garbage disposal, faucet, toilet guts replace, bath sink drain, electric outlets, switches, fixtures.

I recommend getting a general contractor who is experienced in ADU's.