This thought has ran through my head for quite a while. Although, it is a large amount up front, I feel it can be very useful if I use it to sell domain registration myself rather than going through another company. Does anyone have any experience with this as well as ideas/suggestions?

Depends on how many domains you sell.
ICANN fees are not cheap. If you are only sellling a few hundred domains a year it's not worth paying the ICANN fees.

That's true but what I'm saying is if one can afford to implement this into their company. As long as they have good marketing campaigns and a way to attract new domain customers they can benefit from this. Of course, I'm not going to get it when I'm not generating enough revenue to cover it if it does become a loss and it hurts my company financially. All depends upon your client base as you stated, if I know I could pay it off and profit by investing, I would jump on it, until I have that assurance I am sticking with reselling domains.