Not sure that very many responses to this thread are serious, but I'll share some experiences. However, kindly do not PM me to be spoon fed. In both of these businesses you've got to have the confidence to go out, knock on doors, build relationships, fail, fall on your face, learn heard lessons, get back up and try again until after about a decade, you get good at it.
Flipping houses: Can be done, up market and down market. The trick is not to pay too much on the front end. First few you'll being doing a lot of labor yourself. Managing $10 to $15 an hour labor is an art form all of its own that takes a while to learn.
The past two years have been the perfect time to get started, since homes can be bought for the price of a used car. 90% of making the home sell-able is cleaning all the detritus that people don't clean and cutting away all the over grown landscaping.
Going ugly early is a good strategy as long as you avoid water / flood issues and power lines. Aim for good school districts. Branch out and look at surrounding Counties. Too many investors on the Court House steps can drive prices up to an unprofitable level. Find what you want, bid a dollar over, move on. In popular Counties I already see investors driving prices too high ... like aviation .. protect your margins, margins are your safety if something goes bad.
Anything will sell at some price. It is better to work with friends and buy several houses. If you screw up and get a dog, you'll be diversified. Further, with friends you'll be more responsible with the structure of your corporate entities and do deals that make more sense.
Rentals: This is the best market I've ever seen for rentals. Friends are buying homes that will be paid off, from the rent, in two years. Once you get your first home rented, you can finance it to 80% LtE and use that money to buy the next. If your City has a direct paid Section 8, or housing subsidy, this is good business. Helped a friend get a house for $22,000, he spent another $5,000 and had it rented in <45 days for $1,200 a month. It was 2006-7 construction and bank appraised at $125,000. Obviously he hit an unusual home run. Of course he's using the proceeds to go buy more houses.
... and if you are thinking "I'm some poor FO that can't come up with $500, much less $50,000" then just either go to the local airport and find out who's already in the business, or take a nice Thermos and some clean cups to the next auction at your local Court House. There are a ton of wanna be pilots amongst the crowd. Offer them a cup of coffee and strie up a conversation. Most need a cheap, responsible, person to run stuff down and check on projects. In exchange you'll learn how they manage to show up on the Court House steps with a couple million in Cashier's checks hanging out of a pocket. In fact, the best thing you could do is find someone enthusiastic about the business and learn from them.
We might be the shrimp living on the bottom of the ocean. But the bottom of the food chain (in real estate) has its place.