As the property is new to you, assuming you used a home inspector to inspect during the inspection period of your purchase contract, are there any discrepancies noted on the report that relate to this issue (assuming it actually is an issue)?

Obviously there is a big difference between 30k and 135k, so there has to be a discrepancy somewhere.

If there's a big discrepancy on it, talk it through with the broker and explain what you're seeing and why it doesn't make sense.

If there are drug dealers and prostitutes they're doing a damn good job at hiding it.Unfortunately, there seems to be some sort of discrepancy with the city appraised valuation.

Trans union MySmartMove verifies SSN numbers, and notifies you if there is a discrepancy. 

Many times inquiries about invoices, documentation of repairs, delays on repairs, discrepancies on charges, have gone unanswered, delayed or answered in irrelevant ways, but always nice.

The ones that aren’t and I find any discrepancies are automatically declined.  

It's okay to shop for rates a little, but you shouldn't find huge discrepancy's from one lender to the next on the same loan program.

The problem I foresee for you now is, if/when you take this to court, the judge is going to be presented with two very different and conflicting pieces of evidence (an invoice for $1,500 from you and a lawsuit for $18k from you for the same property/damages) and you're going to have to explain the discrepancy

Also, if the escrow isn't with the title company and there were to be a discrepancy or seller wanting to back out for whatever reason you don't have a binding contract if there isn't escrow and it was stated there was per the contract.