2nd mortgage note - Can I foreclose?

[Henry Li]

Hi all, 

      If I have a 90k 2nd mortgage note on a property worth about 600k which the first mortgage is 340k, leaving enough equity on the house. What is the best exit strategy? 

      A bit background, I did a flip project with my friend/partner about 2 years ago. He is the contractor. About 1 year ago the project was nearly done, but we had many different opinions ... long story shot - He bought me out 340k. I lent him 50k before for a $1000 monthly interest for another project and he wanted to hold on to my 40k profit until the property is sold. So together I lent him 90k in the note on this property. He stopped paying me interest for about a year which I sorta agreed to verbally because I know him for a long time. I don't mind to collect all after the property is sold. But now,, he put the property off market and I don't know what the heck he is trying to do. 

Now Question - If talking to him doesn't do to trick, legally what else option do I have? I have both note and personal guarantee. Would selling the note be an option too? thanks