Organizing My Own ADU Construction Project

[Robert Reynolds]

I live in Los Angeles and am looking at building a 2 bed 1.5 bath two story 800sq ft ADU on my property. I've priced out the project and it seems to cost around $110,000 for everything. However if I hire an architect/engineer ($7,500), get permits ($8,000) and hire a contractor ($150,000-$165,000) the price comes in closer to $165,000-$180,000. Is it really 30%-40% cheaper to manage the construction project by myself? Any suggestions or books or podcasts you recommend before starting the project? My expected rent is $2,500-$3,000.