DIY LED basics: getting started building your own grow lights

First I found this on Banggood:

10W 20W 30W 50W 100W 380NM-840NM Full Spectrum High Power LED Chip Grow Light

http://www.banggood.com/10W-20W-30W-50W-100W-380NM-840NM-Full-Spectrum-High-Power-LED-Chip-Grow-Light-p-1126023.html?rmmds=newArrivals


Then I got the idea to look into what it takes to build my own LED grow lamp.
Might be interesting to try. Though I am not sure yet, never worked with high voltage stuff, it can be dangerous.
Maybe it is wiser to just buy a working lamp, but good LED growlights are expensive.