Tell us in full detail about Brazil agriculture - only for experts in agriculture

Only for those who lives in Brazil! We want to open wholesale agricultural/farmer marketplace (website) in Brazil. Marketplace is intended mostly for corporate clients but may be used by individuals. We need all the information about Brazilian agricultural/farmer market. Please provide detailed answers to all 26 questions. How is Brazil agricultural/farmer market designed? What pitfalls do exist on starting agricultural business? Who is the buyers of small farms/households? How do small farms search for new buyers? Are the situations when farmer has excess he/she cannot sell to somebody? How do BIG farms search for new buyers? How large are the parcels/lots of agricultural goods that trade in inner market? Does wholesale trade prosper (between non-monopolist members of market)? What commodity have we to choose for starting our project? We plan to find first sellers and buyers of that commodity and connect them. What goods are not worth choosing? Maybe it's too difficult to implement our service to supply chain of that good. What local marketplaces (websites) for agricultural goods do exist? How popular are that marketplaces? How to implement to farmer/large producer (for example greenhouse) supply chain? Do they already have assigned contracts for all produced goods? Do neighbour farms sell goods to each other? Is a catalogue of farms/households/latifundiums/large producers? We need a contact information. Do all exported goods require special international export license? How do service industries companies search for suppliers? For example, there is a restaurant. It needs oranges. Do managers just use Google? Is there the government's support for agricultural startups? What marketing channels (except Google search) are worth using in agricultural field? Do the Brazilians use the social networks actively? How is trading in CEASA и CEAGESP markets carried out? The whole batch of commodities physically transfer into warehouse? Who delivers commodities after buyer and seller sign contract? Do delivering services widespread? How do retailers search for agricultural commodities suppliers? How is delivery of commodities performed after retailer and farmer/large producer sign contract? How is wholesale commodity trading carried out (not in commodity exchange)? Who participates in the trading?