A commercial real estate agent will know the "ins and outs"; know the "what ifs"; can help refer you to financing professionals, developers, attorneys; can give you the demographics.
Another option, is for you to seek the advice of a real estate attorney that regularly practices in sales and leasing of commercial property. That's what I would do, but then I'm biased as I'm also an attorney.
What knowledge does the agent need to have to conduct that specific transaction, and do they possess that skill and knowledge? Is an understanding of income statements, cash flow analysis, cap rates, vacancy rates, rent rolls, and internal rates of return necessary for the transaction? Most residential agents are not fluent in the above, but there are exceptions. Our firm primarily handles residential, but we have 2 agents who are very strong in commercial.
Not all commercial transactions require the knowledge above. On smaller commercial buildings, a value can often be determined by using comps. This may be especially true for an owner occupant of a small building. If a smaller transaction might be given less attention by a commercial agent who is frying bigger fish, then an agent who primarily does residential might be a better choice. The residential agent might better know the neighborhood and values might rely more on comps than income analysis.
Deborah Madey - Broker
Peninsula Realty Group, Inc.
Bottom line, yes, a residential agent can transact on commercial property deals, both sales and leasing as no additional license is required. Just a real estate license.
Anyone, realtors or non-realtors can access http://www.loopnet.com, the nationwide MLS for commercial property.
Of course, any potential investor should check the credentials, references, education and production of a prospective agent prior to getting involved in a commercial transaction with said agent.
If a potential buyer or seller is concerned about a particular agent with regards to commercial transactions, ask for detailed references including names and phone numbers and then make the effort to check them out.