Owners gave up on their house.... Short Sale Opportunity

I have found a house that is going to be foreclosed on the 28th of this month and the owners are going to let it foreclose. I have a good relationship with the owners and am pretty sure I am the only one in the area who even knows about this opportunity! I am building a Short Sale packet currently but want to make sure I have the upper hand on the bank.

What is the best way to proceed with this situation. Should I buy the right to redemption from the current owners and wait until the property forecloses?

Buy the right of redemption and proceed right away with the short sale?

Ignore the right of redemption and go forward with the short sale.

This house is a mess, they owe almost 150k on the house, and comps in the area are around 170k max. Very small house that will need to be taken down to framed walls and completely rebuilt inside and out. I am looking at 50k in repairs min. The BPO agent is going to go through me to get into the property for their inspection. Any tips for that meeting other than pointing out everything wrong?

Trying to be sure this short sale becomes a success. Questions and ideas are appreciated!