Does someone has any suggestions how to make 17 BTC with 7 BTC starting capital in short period of time?
How short time you need?
well theres a lot of way, but those way are all risky.
and in some way you need a knowledge and skill.
like in forex trading,trading alts, and sports betting.
but theres more, you can have loan business, and gambling.
but in gambling its a super high risk. and lastly.. i think,
investing in a gambling site will be a wise one.
but be sure that the site will be really legit. Goodluck.