I don’t know what the process is to dispute valuations in that county.

Then consider the amount of time required to handle inquiries, bookings, complaints, cleaning, repairs, credit card disputes, maintenance, questions about how to operate the remote control, dealing with vendors like landscapers, and so on.There's much more to it than just throwing it on AirBnB and watching money roll into the bank account.

You have an opportunity to set you and your brothers up for a bright financial future, but you also have a risk of creating conflict and disputes which are damaging to your family.

I suspect when you look back you will find you did the same.If you got an inspection on the property you may want to reach out to the inspector if anything was obvious but I don't think you will get any help there.You could also try to get an attorney to send a certified letter saying you are considering legal action if you can't come to a resolution but any additional fees may not be worth it.If I were in your shoes I would remedy the safety issues (electrical, plumbing, etc) with licensed contractors making them pull permits, consider this a lesson learned, and move on. 

Lawyers handle closing on the east coast they don't handle these piddly disputes.. at least I doubt they want to .. how can they charge enough to cover their time. cost less to have a cleaning service just go clean the house.. seesh.. what drama.

Hope it's simple title resolution. 

I highly doubt OPEC cutting production is nothing more than a short term resolution - if they even stick to it (many of those countries rely on oil & gas for most of their $$$).

@Russell BrazilThis is a listing agreement dispute and not a buyer- seller dispute. 

Provided real world tips & resolutions to real problems that investors would face.. something that the average BP user would get something from.  

You should have your fee agreement in writing with all the contingencies and amounts agreed upon - otherwise disputes, disagreements and disappointments are inevitable.