Promissory Note with 15% return

[Steven Zai]

Hi,

I was approached by a realtor/broker that also buys/flips and wholesales properties and he offered me a deal where I would earn 15% return on a property he is going to rehab and flip.  

The terms of the agreement are a 15% promissory note secured by the property with return of principal and interest in 9 months,

Just wanted to get your guys thoughts on this and if anyone has had experience with this before?

Thanks!