I have a few lots in Tujunga CA where I would like to put up some new units. I am new to RE, is this a good idea?  Plans are to immediately sell after completion of construction and potential use revenue to start an even larger project. 

Rough (i mean very rough estimates)....

say 3 units  @1,300 sqft

 price per sqft 220-250 (Thinking maybe pre-fab home)

Sell at least for 310 sqft.

Will dive deeper into numbers. Additionally, these units would be on "rare" horse lots (allowing horses- tough to find in Los Angeles).