Recommendations for taking this old house solar, and better...

I've seen mentioned on REALNEO and many other sites in town that there is a 1 million MgW solar challenge from the Cleveland Foundation to encourage adoption of solar power in NEO. There is mention of a solar challenge workshop on this later this month, but no details at this link [1]. I know people interested in solar for two very distinct properties I can influence, and I have the attention of some developers as well, but none of those parties will go to workshops, and I believe the best thing would be for a professional to survey the sites and spec solutions (as innovative as possible), so I really don't know where to begin.

Green Energy Ohio (GEO) [2] is a sponsor of the upcoming workshop and seems to have the most info online about solar but the site is confusing. E4S is cosponsor but their site info is not specific. Can anyone recommend a short path on how to get solar potential assessment of a property and suggestions for other alternative energy and conservation approaches. The properties I can influence are:

• A historic mansion in Shaker Heights, an a very tree covered acre, with slate roof - very good sun exposure on the roof, which is fragile and expensive  slate, and a sunny souther exposure and back yard - I believe this property has potential to add some solar and the owners have plenty of money to pay
• The former Hough Bakery Complex in Cleveland/East Cleveland, which has 10,000s of square feet of flat roof with unlimited sun exposure there and for acres around

Suggestions of next steps?