You're smart for recognizing the importance of building relationships...very few wholesalers in my area understand this. 

Tell the buyers if they want a house that is up to current code , buy a brand new one . 

Does anyone have a good inspector recommendation in Chicago northwest suburb ?

A little over 15 years ago, in the late spring of 2009, I was a brand spanking new real estate agent coming off of a miserably failed real estate investment venture.

Find an architect who specializes in this type of work, and who is very familiar  with the building department

., brands, grades).Referenced drawings or blueprints.Agreed working hours (e.g., 8 AM–5 PM, Mon–Fri due to HOA rules).The clearer your scope, the fewer misunderstandings you’ll face.Signatures:Always have the subcontractor sign first, then you sign.

I'm also building a house with Delta.

Square footage is roughly 1600 sqft.Could use minor cosmetic rehab on the outside to make it look pretty, inside is brand new however. 

Purchase price: $630,000 Cash invested: $120,000 Gutted this property, brand new electrical, furnace, propane, finished basement to create separate unit.New garage with rental unit.

That's going out and getting a brand new car with the expectation that you could sell a depreciating asset for more than what you paid for it.