Lastly, a great agent will put your interest first, ahead of any possible transaction, and connect you with great professionals to help you with the purchase process (lender, lawyer, inspector, contractors, etc).The questions you should figure out before starting the search:- What is your budget?

You save realtor/transaction fees. 

Industrial is another alternative.Off market listings/transactions are very common.

I would definitely give a planning department a call.

Even then, ANY monies paid to your sister MUST come from her broker, unless it is a personal transaction. 

It works the other way as well:  Non-Relator Broker = Non-Realtor agents).You also have to pay for E & O insurance and take a certain number of continuing education credits every license period, some of which can be FREE as a Realtor, but most of which costs money.Beyond the above, I suspect you can cover your expenses on just one, full commission transaction each year, depending on the above. 

You'll need to get on a call or get in a meeting with your city's zoning department.

Does the same thing apply to an all cash transaction? 

They simply charge a flat fee per transaction and no monthly dues.

@Rick Pozos  What you are proposing would be viewed as a prohibited transaction by the IRS.