1st Home +new construction Triplex

[Eboni Hill]

Hi, I just bought my first home in Oakland CA with the intention of building a multi-family unit on the same lot (12K FT lot).  I just finished working with an architect to get plans submitted but want to make sure that I'm as knowledgable as possible before I take the next steps.  I'm trying to get ball-park figures on cost to build a ~3K sq ft triplex (3 stories, parking on 1st floor), landscaping/hardscaping, cost of insurance, and any other costs that are sometimes forgotten.  Based on extensive web searches, I think it can be done ~$600K.  And I actually need it to be pretty close to that figure for my plan for funding to work.  I'm refinancing into a renovation loan that allows me to fund construction of 3 additional units up to about 85% of the finished property's value. Including my existing home loan, I'd be looking at a $1.2M loan and expecting a mortgage around $8K (w/tenants to pay ~$6300 in rent).  I'd love to get feedback from people who have built properties/done renovations in the Oakland/Bay Area, or anyone who has experience/sharable contacts for the matters mentioned above.

Thanks in advance to all that respond,

E.N.