Your project cost predictions are nowhere near enough to start a betting site. They're barely enough to even start a functional, professionally built site let alone a highly secure casino (which needs to literally have bank-level security, else hackers will just steal all of your funds before you even start). Being a web developer/project manager for over 16+ years, I'm definitely qualified to make such remarks regarding this. Not to be a buzzkill, but you will definitely need well over $100k for dev/design, and this is if you just have one game like a dice site. If you're trying to actually build out a casino with multiple games, expect to realistically spend in the millions. If you think this is overkill, then clearly you don't understand the dynamics involved in building out such a site. Anyone who claims that they can do it for less has no idea what they're talking about. Just being honest with you, as I hate seeing people waste their time and money with some overseas dev who claims they'll build your site for 1/100th of the price that it should actually cost.
Development set aside, I hope you realize that you need a BANKROLL to start a gambling site. Meaning you'd need to keep a few million in a cold wallet for financial solvency. There is absolutely no way you can start a gambling site without having a large bankroll to cover wins. Just to give you an idea, most of the popular dice sites have anywhere between $500k to a few million USD in their cold/hot wallets. Again, this is for sites with just ONE game. To be completely honest with you, I wouldn't move another inch on this project as I can guarantee you that you will be doing nothing but wasting your own time and money by doing so. Maybe try
Sorry accidentally clicked post. Was going to say maybe try learning a development language yourself so you can get an idea of how significant of a project this actually is.