Roof solar load assessment

I am looking for a freelancer to assess the solar load on my sloped roof. The size of my roof area is 100-300 square meters and is located in a suburban area (See pics). I require a stamped letter for structural and wind load impacts in order to pull the proper permit in Melrose MA, 02176. The roof is in great shape with a 25deg pitch, 4x8 construction, 16"OC. It will have 14 panels on one side and 7 on the other. Panel size 75"x41" and weigh 47lbs each. They will be secured with Unistrut and prosolar mid clamps and smarkey end clips and lag screwed into the roof joists through flashing.