How not to get cheated when buying an apartment

[Galit Garsiel]

How do you avoid paying for an apartment and then getting cheated?

There was a company that went broke, and people have paid them for apartments they ended up not getting, nor their money back. And there was a person who paid someone to build a house for him, and the guy took the money and disappeared, perhaps to another country. There were also people who'd paid a company for apartments that ended up being storage spaces instead of apartments. 

Aside from paying for a house/apartment that alread exists and not being built, seeing the apartment you're going to buy for yourself, signing the contract in front of a lawyer, and checking out the person you're buying the apartment from, what else can you do to protect yourself? What to watch out for?