But right now we are having 2 potential tenants who are both mom and pop  (for the same unit) so they are about the same in term of credit worthiness that's why I only need to look/compare the rates for now. 

Provided that they are creditworthy, are your buyers consistently finding lenders that will refi a lease option and consider the lease period as seasoning?

They don't necessarily look at property metrics first and personal creditworthiness second.

Bob should understand that one’s creditworthiness is determined not only by the income, assets and job continuation, but also their reliability in paying money back in the past.

They rely on credit-worthiness to make a sale, so they will only mail to people with high scores.

I would say this is all based on your income, savings, credit worthiness etc..With that said, yes generally many people can buy more than one property.Partnerships are an excellent way to exponentially grow your business/portfolio.

If all else, round up your payment to assume the "worst case scenario" and see if then the numbers still work.You can of course still get prequalified, which is not a commitment to lend by a lender but based off your credit worthiness and a short application to the lender, lets them know a round off estimate of your financial situation and if they CAN lend to you.

They may want to look at your creditworthiness too.

That said, lenders also look at a variety of factors to assess your creditworthiness. 

The only difference in the loan process was that the lender looked more at the cash flow potential of the property to make the decision to give me the loan, rather that looking at my own credit worthiness.