Be ready for environmental / fire inquiries such as whether fuels and lubricants will be stored on the property, disposal of such things, fire suppression systems, hazardous substance containment, welding torches and other flammable substances, etc.

(this place also had huge unpaid environmental violations) Projected cost was well over a Million. 

The cost to build and environmental regulations are a barrier to build housing.  

One thing that bank recommended to me when I bought commercial property with seller financing was to have a phase one environmental study done because most banks would require when I needed a refi and that way I would know before buying if there were going to be any issues.I’d be happy to chat further if you want, just shoot me a message.

Typically your lender will schedule a series of inspections, (physical, environmental, etc) they'll have a few that they have worked with in the past.

I'm planing to turn the front unit into a restaurant for rent since the property is surrounding by residential and businesses but I'm wondering about environmental issue, in this case who can I talk to to make sure I can build a restaurant on this property before I made the purchase?

There are some environmental companies in town that should be able to easily remove.

An expert may be engaged once the property is “under contract” and the initial due diligence, concerning clear title, clean environmental, financing approval, lease verification, and profit and loss report verification have all been taken care of.  

When speaking with my mortgage broker, she informed me that to buy a commercial property I would need an environmental assessment (6k), and a commercial property assessment (2.5k) and then a 35% down payment on top of that.

Landlords must also give renters a pamphlet on the dangers of lead-based paint prepared by the Environmental Protection Agency.