I will tread into waters that I have not mentioned before, and that is, as the title or header suggests: Gambling, and specifically using occult powers for the purposes of making or winning as much as possible.
I have experimented using divination for this purpose, mainly predicting the outcome of sports matches by doing so. And the results were mixed, hits and misses; ultimately, it has been interesting, but futile and the conclusion/ assessment I can make is that divinatory methods are unsuited for doing this. No matter what way you’d spin it, it still worked sometimes and not at all other times. The reason for this is that it pertains to the lives and existences of others, and not to the wagering of matches or any kind of team vs team situation. Not in this context.
So what could work? Summoning an entity for the results is an option, and I know one or more that have a 90% success rate. A friend of mine tried the lottery by asking me to ask a spirit for the result (4 number draw), and it was very accurate in the sense that one number was incorrect or that it was not in the correct order, or that it did appear but on a drawing that took place a week or so later, or in another country’s lottery.
I could research the matter further, but it would take considerable effort and resources to do so and I don’t intend on doing so, since I am not fond of gambling at all. Why? The sheer definition of what it is, just that: Gambling. Its unreliability is a major turn-off for me.
Even then, it is still a good stretch; it boils down to you asking a painter to paint a 3-story building in one day. Talk about a stretch. But it can be done. Not worth it for me however.