One big thing is how long the casino has been around. If it is relatively new, it is really hard to judge how successful it is or will be. If it has been around for awhile then there is probably a good reason. This is generally because of how trustworthy they are and how good their customer service team is. You also want to make sure they have certification from a reputable source, like CIGA, TST, eCOGRA, or KGC. Security is also a key point. After all, if you are gambling real money you want to make sure that it isn’t going to be subject to any sort of corruption.
Customer service is usually a very big selling point too. You want to make sure that any problem that you may have is handled in a timely manner and that you never feel like an imposition. A site with limited customer service hours should be avoided. If the casino website is running 24 hours a day, their customer service team should be as well. They should also provide several different ways to be contacted like phone, email and live chat to ensure you can get in touch with them when needed.