On the surface, it sounds like an easy get-rich-quick plan: Buy a multi-unit building, sweat equity into it, rent out the units, then sit back and reap the profits. While many people have created a large nest egg with a great cash flow, purchasing such a building is not as easy as it seems. And there are pitfalls to being a landlord. In fact, most real estate experts say that buying and managing a multi-family unit building is akin to running a small business. That's why there are a number of th...