Acting as Lender on land deal?

[Zach Zander]

I've been presented an opportunity to provide a $40k loan on a $45k land purchase. Within 6 months the Buyer would repay the loan plus $20k (50% ROI). He'll be selling the land for $175k, making a sweet profit. Land is worth $200k.

Is this low risk deal a good opportunity? Should I be asking for more just because he's going to profit so much? 

Other thoughts or considerations? I'm thinking it'll be a recorded Commercial Loan, but don't really know whether there's a better option (my first time serving in this capacity).

Thanks in advance! 

Zach