Startup pitch, market size, Various strategy and scenarios, marketing plan

I need help with the market size and defined a multiple marketing strategy that could lead me to forecast financial plan. It is social networking platform for small communities such as neighborhood residents and to bring together those with common interests. We target residents of neighborhoods, sellers of services and products in the neighborhoods. Such as maintenance workers, local stores, babysitters, freelancers, productive families (homemade food) and other handicrafts.
Scenarios of a marketing plan that I can return to during the preparation of financial and growth forecasts, as well as the implementation phase.

Requirement: Market size, strategies, Customer acquisition cost, Expansion plans, slogan, Possible options.

Please let me how you can help me. I am looking for someone who I can always return to for advice and work, permanently, as long as I lead the project