If you have 500k to invest......

I would invest in multifamily syndication because it's easier to scale (typically $35k min investment in each syndication deal). I'd also consider investing in ground-up developments, since they offer greater returns (typically $100k min investment in each syndication).

I highly recommend you not to put all $500 k into one deal because diversification is key!! Especially putting $500k into your first deal. You'll most likely make a lot of mistakes. 

To minimize risk, you should invest in markets that have a healthy growth trend, such as Raleigh, Phoenix, Las Vegas, and many more. You should also diversify your portfolio by investing in different areas with different syndicators that all have a solid track record. Diversification is key to minimizing risk, so you should also consider putting some of the money in stocks.