I was wondering if there is a required amount of bitcoins you need to have before you start trading? Also, a little out of topic, but is there a required amount that a person needs to be earning per month before he could start buying bitcoins?
Yes and no, there's no requirement on the exchange-side how many Bitcoin should you own before you start trading. But keeping in mind that the exchange fees do stack up alot if you're active trader and should be taken into consideration. Anything less than 1000usd gets eaten easily especially if your win% isn't extremely good.
I personally wouldn't start with anything less than 5K worth unless going high propability trades with margin.