Lead: Within various CRM systems a lead is a person. In the solar space, a lead is a physical address where a solar installation could potentially occur and the responsible person(s) living at that address is a contact. New leads can be generated in Enerflo by clicking + New Leads in the menu bar of the user's Enerflo instance. Leads may also be imported via the Lead API (see documentation link below).
Deal: Deals are created on and attached to the lead. A deal is the personalized solar proposal for each customer and includes the consumption profile, title check (if enabled), design, proposal, additional products, financing information, and install agreement.
Deal Type: Deal Types are created for each partner to ensure existing deal information is kept together in the same location. A deal type is a way to create a deal with various design teams and/or installers needed to create the customer's proposal. Deal types vary based on installer you need for the project at hand. Installers may have different deal types for each sales org and different situations.
In short, the lead is WHO and the deal is WHAT is being sold.