Is it good to invest in a condo?

I was offered a good payment term for a condo unit in the Fort area. Since I was offered a pre-selling price, I was told I can sell it in the future with good returns. I may also rent it out at a good monthly rental price. I may also decide to use it when my children goes to college, but I think Fort is a little far from the big universities.

Is buying a condo unit a good investment? If I'm going to sell it later or rent it out, how many bedrooms should I get for easier disposal?