Also, the bank wants to be first lien holder.

If anything happens to the property, it is the lien holders loss...title transferred, but there is still a lien...this is a very problematic situation.

I bought one of those swiss army knife looking key holders but it isn't great because the keys tend to come unfolded from the case on their own. 

We set up an entity that will take title to the new property (called an exchange accommodating title holder). 

you typically do this at least a week before the sale and verify the amount owed to a lien holder to try to make sure there is not an accidental foreclosure sale of that property. 

What I am looking to do is leverage their investment for just one deal at a time allowing them to be first lien holder on the property and then prove the value and work towards a relationship that will allow me to use the funds for say 6-12 months, with payback terms and interests allowing me to turn that money over a few times vs. just one property at a time. 

Buying house and selling it to new owner while you become the note holder on the house.

Just pay off the lien holder the tax amount plus the overage etc.  

@Raven Walker I would not recommend anyone to buy property with tax lien because tax lien holder may start foreclosing process once the lien passes 2 year redemption period.

Once the now performing, modified note has a 12-24 month payment history, the note holder should have an asset with a significant capital gain.Note secured by commercial property carry rather light regulatory baggage.