How to Properly Reject a Prospective Tenant?

[Ayodeji Kuponiyi]

Should my rejection letter read something like this:

We're sorry to let you know that the property at [address] is no longer available. At this time we've rented this property to other applicants. Thank you.

Do I need to add a reason why their application was declined? In this case it's income and employment is 3 months. 

The rental application fee is non refundable.