Cool post, but I think you can only do 3 round trips...the 4th makes you a day trader.
From TdAmeritrade...
1. What is a day trade/round trip?
What is a day trade/round trip? A day trade occurs when you buy and sell (or sell and buy) the same stock or option position during the same trading day.
2. What is a pattern day trader/pattern day trading account?
What is a pattern day trader/pattern day trading account? Any margin account that executes four or more day trades/round trips within a rolling five business days has shown a pattern of day trading. The account will be flagged as a pattern day trading account and subject to the National Association of Securities Dealers (NASD) Pattern Day Trading Rules.
3. Day trading
Day Trading Margin Requirements/NASD Pattern Day Trading Rules What is a day trade/round trip? What is a pattern day trader/pattern day trading account?
4. Day Trading Margin Requirements/NASD Pattern Day Trading Rules
Effective September 28, 2001, the National Association of Securities Dealers (NASD) enacted changes to day-trading margin requirements, which may affect your account. The NASD provides that a pattern day trader is any account that executes four or more round-trip day trades within any rolling five-business-day period. Day trading is the practice of purchasing and selling, or short selling and purchasing to cover, the same security (equities or options) in the same trading day within a margin account.