If the loan is current, a short sale, a loan modification, and a refinance should have no negative impact upon the homeowner's credit report.
If the homeowner is behind on his payments, but foreclosure has not been initiated, then a short sale, a forebearance, a loan modification, and refinance won't negatively affect his credit report any more than the late payment history already has. Good credit standing can be regained in about two years provided the homeowner does not incur any new credit blemishes
If the homeowner is facing foreclosure, then most likely his credit rating is already destroyed. Bankruptcy will stay on his credit report for ten years. Foreclosure and deed in lieu of foreclosure (if the lender will accept it) stays on the borrower's credit report for seven years.