Actually, the fact that you don't have any plans yet is a BIG part of the problem, as it sounds like you've already committed to buying the property.If you don't yet have rehab numbers, how can you possibly know whether it would make a good flip and/or rental?

I see the problem as well.

This would not completely solve the problem as its the original floor boards at 3/4" or so, so I would have to shim the left side also a bit to buy the complete 1-3/8" level. 

So what's the problem?As

However, that might lead to a ceiling problem as @Larry T alluded to.   

I recently found the same problem as @Daniel Ryu; is it because we are not "Pro"?

I can use that "problem" as a negotiating point and get the property for a lesser price. 

I'm not sure if this is a hard money lender problem as much as a plain old scammer problem.

You are in a good position, you credit is excellent, you have no debt, the problem as I see it is that you live in a very expensive city and its is generally hard to get decent cash flow in SF. 

They'll give you a report showing what it needs, whether piers need to be added and how many, whether existing piers need to be shimmed up, and so on.It may be there's no real problem....a certain amount of foundation settling is OK.