So low market cap is better for investment?
It mean we dont have huge amount of coins ready for sell?

It's definitely not a better investment, it can earn you more profit indeed than high marketcap coin but it also has more risk as investment compared to high marketcap coin. Low marketcap coin is cheap because they haven't proved themselves or they haven't got enough coverage. If you want to invest in a low marketcap coin, then you have to find one with good dev or else there will be a situation where the project is abandoned.