I have a (presumably) great idea for a business. My question is, how do I find out if the idea is actually great? Nobody (or very, very few) is doing the business I'm thinking of, and I can't find a way to actually tell if it has success potential. I'm from Eastern Europe, and my idea mainly applies to other countries. Asking on the internet will just put the idea out there. Is there a way to test such an idea without jumping in it and potentially wasting a lot of money for nothing (if that is the case)?
Get someone to pay for it. You will have to put it out there sooner or later.
A business without sales is a hobby. If lots of people like what you have, but aren't willing to pay for it then you have a good hobby. If lots of people pay you have a good business (assuming you can make money).
Maybe you can launch some beta-version of your idea in order to test it. Implement it partly and see the feedback. Of course nowadays ideas are stolen very often, so maybe consulting is not so helpful.
A lot of people has partners for their startups. Maybe you should find the one who you trust. It's better to discuss ideas with someone else, who can give you recommendations.
Good luck!