Can I cancel a Refinance after I sign the documents?

[Juan M Restrepo]

Hey Guys, 

I decided to refinance my rental property since rates are extremely low. I sign a couple of documents ( Appraisal report, Proof of delivery, hazard insurance, loan estimate, Lock agreement) but my current loan Status is Conditional Underwriting Approval. Furthermore, My loan officer also wants 2 pay studs and the lease agreement. Thanks to J Scott's Book (Recession proof real estate investing), I decided to sell the property instead. Do you guys know if is too late to back up from the refinance?