Ebay find to finish tow package

I bought this 2013 SL 4x4 last month. It has the big tow package (gears, mirrors, trans guage, 27 series battery, receiver...etc) I found the cable for the controller in the glove box. I don't have a trailer as of yet but plan to buy a 19' - 23' toy box in the future so I started to look at controllers to be prepared! I found this Hayes Genesis on Ebay, boxed new, for $22. An internet search showed others selling it for $80-$125. I don't need anything fancy and it looks easy to install. Wiring is already done!