My offer is based on the "satisfaction guaranteed" program - if you are not satisfied with my services, you don't pay for it.
I have been involved in a number of projects and my work has always been considered valuable.
Couple of references:
"Peter demonstrated a high degree of professionalism and quality of service. He shows remarkable flexibility, innovation and ability to meet tight deadlines. I highly recommend his services."
project manager in one of major IT companies
"Peter is the best Java programmer I know."