Should I buy a condo or should I invest the money in the stock market?

I can buy a condo for 187k cash, and my monthly fee going forward between taxes and maint would be $400. Or I can take that same 187k and put it in the stock market and continue renting my apartment for $925 per month. What should I do?

Unless you understand the stock market, you are better off paying for the condo. If you put the money in the stock market you have to make up $525 a month plus taxes (probably around %30). That's means you need to profit $750. That's less than .5%/month return. That should be extremely easy in the stock market, but you have to know what you are doing. With $187k you could probably find someone to handle your finances for you, buy your new condo, put the money where needs to go and you never have to look at it.

This is easy. If you rent, your expenses are $11,100. If you buy, after closing costs, your expenses per year are $4,800.
If you invest the $187,000 you can expect to get about $14,000 after paying taxes. Figure $3,000 for utilities and you will be living for free in the rental...$14,000 - 11,000 - 3,000 = 0
If you buy, it will cost you $4,800 + $3,000 utilities or $7,800.

I own my own condo. The value is $120,000 and I get nothing for it. On a good year, the value will increase by 3%.

Right now is not a good time to buy a condo.