Dear Dave, I’m 24, single, and I make $60,000 a year. I’m also debt-free and live in an apartment, plus I have about $550,000 in a brokerage account that’s made up of 75 percent mutual funds and 25 percent single stocks. The money in the brokerage account was originally an inheritance of $280,000 that has grown since I received it in 2007. Am I putting my money toward the best investment possibilities right now? Drew Dear Drew, You’re in a nice place! I’m glad you’re taking your finances and your future so seriously. First of all, I don’t play around with single stocks. There’s just too much risk there for me. Since I don’t invest in single stocks, I don’t recommend others do it, either. I look at two things when it comes to investing—real estate and mutual funds. I always pay cash for income-producing real estate. And when it comes …