I believe some freelancers would help you do the job with the right amount of price. It would take a lot more effort to build something like Betfair and you would need to develop your site and of course, the marketing side so that there would be users in your site. It would be a big project and there are a lot of resources like YouTube when building stuff like it.
Yeah, and like I've often said, this days, building a casino has become way more easier than we all can ever imagine, but the real work is in getting users, which also translates to how to effectively market the casino.
There was this book I was reading one time and I came across a place where the writer said that in the old day, building a website was a very big hassle, it required a lot of work, experience and expertise, but the reward was that, getting users was not a problem at all, that is you can get millions of users even without any form or marketing.
But today, things have completely changed, the table have turned around, In the sense that, building a website have become so very easy, but the hassle now is on getting users, and sometimes, you discover that you spend even money on marketing than you spent to built the site, and spend to maintain it.
I believe op already knows about this though, that is, the importance of marketing.