Newbie Needs Help (Over-My-Head LOL)

[Kasaung Anderson]

Great day to all and God bless! My parent's property is located in a great area of Nassau County, New York. I just found out from an architect that the land has enough square footage (properly zoned) to build (2) single-family houses with a little over 2500 square foot and/or (1) two-family house with a little over 4500 square foot. It's gonna cost between $150-$200 per square foot to build the new homes. The existing single-family house balance on their mortgage is a little less than $200,000. I'm trying to live in one, either the single family home or on the lower part of the two-family home, and rent or sell the other single-family home or rent out the 2nd part of the two-family home. This is all new to me, so, I need help figuring out the comps, finding cash, and which is the better project to proceed in? Thank you!