They may not know the quality of the work (due diligence on your part enters here) but they'll know the persons personality and credit worthiness......

@Ashley Kinnaird Of course the lender will not allow you to assume the mortgage, because they have not check every crevice of your person to see if you are credit worthy.

They will look at the appraisal and creditworthiness. 

The company says they will pay every month, so naturally I’d like to run a check on their credit worthiness and financial soundness.

It's important to note that permanent/long term financing for investment properties will be especially difficult to procure and if you're able to find a lender, then I would expect for your deal to be highly scrutinized as well as your creditworthiness.

These lenders are able to do loans for people who are credit-worthy, but don't fit the system that the credit score was made to measure (i.e. the Dave Ramsey community and young people, ha)The BEST resource for you would be to talk to a local real estate ninja who can guide you to the right lenders for this. 

I am considered creditworthy.

All depends on credit worthiness of property manager/leasee.

We had a lot of questions about process, all were explained in detail.We also walk away with advice on building creditworthiness.

it's a pretty easy decision in my opinion:  Bail on the house, put the 150,000 away and rent for awhile while you're repairing your credit-worthiness.