Attorneys, agents, lenders/brokers, contractors, insurance agents, property managers, accountants, architects, property tax consultants, income tax consultants, Estate planners, Environmental companies/industrial hygienists, surveyors, structural engineers, etc.

The DEC is the department of environmental conservation.

If buying homes with UST, I have an environmental study done.

Environmental can be $5k.  

I am a former environmental, safety and health professional of 27 years in the process of a career change.  

You may also find the information online (which we have here in MD).This is an environmental issue and not something to tinker around with - I'd get on this immediately if you haven't already. 

I'm fairly new myself, so I can't really help, but I think I'd get as much info as I could about the land (zoning, what the local cap rate is, what things are surrounding the land, is the neighborhood on its way up or is it dying, has your family ever had an environmental impact study for building an apartment complex there, etc).

You could then jump through hoops and get a "Letter of Environmental Protection", but that will raise your insurance and lower the value of the property, but at least you could legally rent to families. 

Also I was wondering about limitations on property use in the finance agreement to deal with the potential that the buyer might cause environmental damage to the property.I have never financed commercial property, so I'm open to any experienced investors advice on other concerns

It could get a "Letter of Environmental Protection" once the work was fixed and done legally which would allow the house to be rented to families again, but it will also raise the insurance rates and lower the value of the property.