In demand will be at least 3 months for legal, surveys, etc.

I would also check and see if you need a site survey.

I always suggest getting a survey done, and if you have past soil sample reports even better.  

In my "9-5", I work on a lot of as-built surveys for architects/home owners adding ADU's.

You need a good asbestos and lead survey, then you can obtain a firm - fixed price for any abatement which is needed. 

Soft cost (like the expediting fee, arch & eng fee, filing fees, zoning exhibits, topo land survey, Asbestos testing, etc.) can easily be $50-60k excluding Construction cost.

Then while you are all excited and happy they get you fill out the "how we did survey"which when we filled it out was befor we tried to put their practices to use.

Sounds like a liability so I would get the survey and if it is on your property remove it and avoid future litigations. 

In other words you didn't have anyone trying to corner you into doing something you weren't comfortable with.At the end, on the survey, they asked what I thought the value of the summit was.

Min commitment is a $3k site survey plus feasibility study and its applied toward your build when you proceed.