Leasing a property for 9+3 Years

Hi I am Sushant from Odisha. I had a Roofed property of 4000 sqft at a rural belt of Odisha (Not under Municipality/ NAC ). One of Shopping Mall company is asking a single lease of my 4000 sqft roofed property for 9+3 Years. Should I lease them directly for 9+3 Years in a single Lease agreement ? And how can I protect my rights ? Please let me know the dos & don't while finalizing the lease agreement. So that I can protect my self in future without any rights issue in the said property. Regards- Sushant