Anthony, it looks like you have a compressor to run a 3/8" air diaphragm pump. Thanks for the recommendation on the 200' of hose,Shawn. Should you plan on marketing your roof cleaning to larger homes or commercial locations, increase the length of hose to 275' or 300'. You can use the 1/2" or 5/8" chemical hose. Remember to use a length of ag hose on the suction side of the pump and try to increase or double the size of the supply hose from your tank to your pump in comparison to your spray hose attached to your wand assembly. The ag hose is a good choice because it will not collapse in this application.
You can use a Titan hose reel with a stainless steel manifold to roll up your hose instead of having to coil it.
Call or email me for pictures. I will send you assembly pics of different ideas to choose from.