Isn't it better to charge some percent of overall profit than a one-time fee?
How would you enforce this? Unless you send the money to Gunthar and he does the trades. The problem with that one is, that people won't trust and call it scam. Here you get the bot and are your own trader.
it is NEVER good to allow others to trade FOR you ...
ever ...
the complications that come about are way too much - and the issues that can arise are even worse ...
so doing your own trades ( as cz3kit mentioned ) - with NO interference from servers and centralization of funds ( especially policing percentages from YOUR trades ) are the best way to do it - with your own licensed bot - using your own parameters - on your own responsibilities and shoulders ...
learning is fun also ...

...
#crysx