Subject to Deal - With Curveball

[Joeny Ortiz]

We have a motivated seller who is willing to do a Subject To deal - amazing. The problem is that he wants 12K cash to settle a lien, placed by a bank, on a separate property that he lost to foreclosure.  

The seller will allow me to contact the lien holder (Bank) and settle the lien.

Here is my question:

1. What do I need in order to act on behalf of the seller with matters pertaining to this lien?

2. Will a bank reduce the amount of the lien?

Thanks,

Joe