Real estate investing strategies are so numerous it's hard to "pick" one.
The problem with "picking" a real estate investment strategy is they're not like mutual funds.
To be a real estate investor, you've got think like a businessman. or entrepreneur, is a control freak - they want to figure everything out and have the satisfaction of control.
What strategies are required to be used to become a successful RE Investor?
Well a person's strategies are going to depend on your credit, your starting capital, your goals, your ambition level, and your tolerance for risk.
Okay, for example if you have crappy credit and no money, then finding strategies in which you do not need to get normal financing or have money for repairs is essential. You could look into lease options, contract for deeds, subject to's, wholesaling, and rehabbing with hard money.
Now if you have good credit, and depending on your capital, your goals, your ambition, and your risk tolerance, you could look into rehabs with conventional financing or commercial financing, residential single family rentals, apartment rentals, commercial rentals, apartment rehabs, or carrying notes on single family, apartments, and/or commercial.
Your credit and starting capital will determine your options, and your goals, ambition, and risk tolerance will determine your preference out of those options.