As developers target land-rich churches that are losing revenue in areas like Harlem and Washington Heights, some churches that lack real estate savvy are losing out. At Saint John African Methodist Episcopal Church on West 134th Street, the pastor is still waiting for a developer to start renovating the sanctuary and building condos above it, after a deal was signed two years ago. To prep pastors for the business of negotiating a deal, a forum will be held next month by the Union Theological Seminary’s Ecologies of Learning nonprofit in Morningside Heights. Hundreds of pastors are expected to meet with real estate and development experts. The seminary is also holding a month-long course on “faith-based development,” which will teach students how to appraise property, select a developer and read the fine print of a contract.