The better the site, the more cost your going to have. I've actually thought about doing the same thing. Here is what I came up with last I checked.
First off you have to have an offshore gambling
license. This is a decent fee (I listed below). Then you have to have a program, or pay a company to build you the software for you. This can cost anywhere from $100,000 - $500,000 depending no how in depth you go, how nice it looks ect....Not to mention that when you first open your not going to make money, because you have to pay you debts for one. Also a HUGE thing...You have to have money in your bank to pay out all of the money your customers will be winning. Once your debt is paid and you get more customers you will start making money. Just like ANY business you WONT make money day one, hell maybe not even for a couple of years.
The biggest thing that will help you is you have to have great promotions and the best in customer support. If people have problems they will not come back.
Jurisdiction License Fee:
Anjounan - $17,500 + $10,000 Legal Fees
Grenada - $40,000 + $20,000 Legal Fees
Antigua - $75,000 + $10,000 Legal
Mohawk Territory (canada
) - $10,000 + $15,000 Legal
Costa Rica - $100 + $5,000 Legal
Alderney - $75,000 + $10,000 Legal
Panama - $60,000 + $20,00 Legal