What does it mean to say “You need to trade 200 lots before you can get a bonus on your balance”. I don’t know what they mean by “200 lots”.
It means you have to trade 200 full lots before you get your bonus. So if you’re trading 1.00 lot per trade you’d need to make 200 trades to get the payout.
Yes. I myself would also be careful with a broker who offers such a bonus system. Sounds not seriously to me.
You should look here:
http://forums.babypips.com/newbie-island/50139-lot-sizes-standard-mini-micro-help.html
and here
Lots, Leverage, and Profit and Loss | How Do You Trade Forex? | Preschool
This is one of the reasons why you need to read the terms and conditions before you accept a bonus and determine if they are acceptable to you or not. Not all bonuses are terrible and most decent brokers always allow you to withdraw your earnings. In general I always stay away from any sort of bonus and never accepted one with the exception of my small account ages ago where I try to new things and tested my strategy.