In my experience, The 3 5 7 Rule of Stocks is almost magical! Never risk more than 3% of your total capital amount on a single trading position. The total risk for all positions should not exceed 5% of the trading capital. Each profitable trade should bring at least 7% more profit than each losing trade.
The short answer is yes. The long answer is that it depends on the strategy you plan to utilize and the broker you want to use. Technically, you can trade with a start capital of only $100 if your broker allows. However, it will never be successful if your strategy is not carefully calculated.