Reasonable rate to pay on short-term private financing?

[Samuel Fowler]

Hello, 

just wanted some feedback from those that have been involved on using private financing to fund previous deals. I am not soliciting for an investor just for feedback. 

I am requesting $15,000 amount on a 6 month term in a relatively low risk investment. The full amount plus interest would be repaid when the construction/rehab note was paid off through a refinance to a conventional mortgage. 

The private investor is a friend of mine that has asked about working together with me on a deal. What is a reasonable interest rate to pay him for his note of $15,000 for a 6 month term. 

Thanks for your input and reasoning behind the numbers you provide