Best insurance while constructing a detached ADU?

[Carl Morgan]

Plans are approved to construct a 1,200 sf DADU on my property that is tenant occupied in an existing 3/1. Location in San Diego, CA.

What type of insurance should I have?  Is the existing homeowner's insurance sufficient?

Obviously we'll section off the area prior to construction, but I'm concerned about the safety (and lawsuits) for all involved.