How will you assure that the client website doesn't detect the incoming ip's are not legit ? Do you use actual human traffic or bots ? If you're using bots then I doubt it will work out as most of the modern websites can easily make out even google crawlers do and that would result in ban of the referral services .
The Service is not done by bots.
Im doing the refs in my spare time at work. Have Access to different Ip's daily (regular like 40-50 ips per day).
With all due respect what exactly would these 40-50 different IPs refs be of any use to the site on which you would create these refs?
You'll not be active from all the account(s) other than your primary (that too chances are negligible)
Owner of the site will end of paying but these refs would not help the site in any way.
Typically site's pay for refs to bring genuine REAL HUMAN traffic who at the end would want to stay active & benefit the site in some way.
For me there is absolutely no point in buying such dead refs which are of no use in long run. If someone has to buy this then better choose
www.gosignups.com which sell dead refs for $0.1 each not 0.002 BTC each.