As Charles suggested, you might buy the note from the bank, the first, go to FC and wipe out the subordinate liens.
You will not be able to get an option from a bank, but could have it under a purchase agreement.
You can not foreclose unless you own the note. Under any other agreement that puts you in one of two possible positions; You could be the Trustee, but this is higly unlikely since throgh the foreclosure process mistakes can be made and the bank would be liable with you acting as their agent Trustee, so forget that.
Secondly, you would be a loan servicer acting in that capacity which is regulated under serveral federal laws.
As to partnering with any attorney in any action of any kind, you would have to be an attorney. An attorney acting as Trustee will not "partner" with anyone. Knowing the attorney and working through that attorney could be a way to obtain the note before the FC, but there is no way they can "cut you in" or allow you to work in their place.or stead !
Since you are not a lender, most likely you will need to find the borrower and have them provide you with a letter requesting that the bank sell you the note as an alternative to foreclosure. Selling a single note to someone off the street without the borrower consenting will be a tough hill to climb, unless the bank is offering the note for sale to institutional investors.