Muy, here are some things to consider.
Pros:
Real estate is probably the best investment out there. I especially like rentals because you get cashflow, the depreciation write off on your income taxes, appreciation (depending on the area), and someone else paying your mortgage down. The condo community tends to get taken care of better than apts. due to most people owning the property rather than renting.
Cons:
Being a landlord and dealing with tenants. Dealing with the condo association. While not always bad, they can enact rules that are unfavorable for landlords. Condos/townhomes tend to have a smaller buying audience so you may have a harder time reselling them.
Things to consider:
Be sure to read over the association rules very carefully to see what kind of restrictions, if any, they have regarding rental property.
Can you be a landlord? The question I was always asked when I started getting into this was, "Can you evict a single mom, with 2 kids, on Christmas Eve, during a snowstorm, if they haven't paid rent?" I know that's an extreme example, but the point is, being a good landlord and doing what's in your best interest as a property owner sometimes requires you to be the bad guy.
Can you function as a handyman? While it may be a beat down to have to go repair a toilet at 7pm on a Tuesday night, after a 10 hr. day at work, it sure beats paying a plumber $100 to do it.
Looking at the prices of the properties you are looking at, I'm not sure how easy it will be to find renters to cover the costs. Obviously, I don't know the neighborhood you are looking in, but the quick and dirty calculation is that your monthly cost = 1% of the purchase price. So the 140,000 property would cost you about 1400/month, meaning you need to find someone who will pay at least that amount in rent to break even. You'll also have to factor in the HOA dues at some point. Just make sure you check other rentals in the area to see if they support the rents you'll need to charge.