It'll be around $100, most likely. Our license manage is better than anything comparable on the market today, in terms of inability to circumvent without nulling it in the code.
It'll be out soon, not sure we need anymore testers at the moment.
Have you met the requirements? http://docs.blesta.com/display/user/Requirements
If you do, what version of MySQL version do you have? Hopefully the guys can help better.