Real estate major Unitech Ltd is in final stages of negotiation with Lehman for a $500-million PE investment in its two commercial projects in Mumbai. The two sides have signed a non-disclosure agreement. According to sources, the investment may come into two SPVs floated by Unitech for the projects in Santa Cruz, and Lehman could pick up stake in the SPVs. Unitech is planning to sharpen its focus in the Mumbai market over the new two years. Unitech already has a land bank of 350 acres in Mumbai and in next two years the financial hub is expected to contribute more revenue for the company than the National Capital Region.Both the Mumbai projects would have a combined developable office space of 2 million sq ft in the initial phase.