How many times one can loose all his trading accounts before really start trading and earn.
I have lost 5 times some small accounts (less than 100$)
And one little big account (400$) in trading.
Amount doesn't matter everything depend on you.
Actually mate it matters, the profit will depend on the capital, you cant't gain a thousand dollar with a dollar unless a miracle happens.
First you need to see if you have the ability to do day trading. If you do not have trading knowledge, you will lose small or big amounts in few trades. However, if you are an expert in trading, then you can increase your capital. You can increase your trading knowledge by trading with small amounts. Which will help you in the future.
Knowledge is the foundation of your skills, every one can day trade but not every one can win in day trading. $100 for me is enough, I don't know it is just maybe for me coz I can make that $100 into $300 after a good trade in a week or two, depends on the market situation. Make it a habit, the longer you are trading the more you add money to it. Invest on your trading life, no one knows what it could bring to you but the risk is worth, perhaps.