The couple runs a very successful vacation rental with these cabins. 

When I asked him if he ever received a letter "we buy houses cash"... he said no.... he never did in many years.I was surprised and thought... maybe there are good opportunities.... vacation homes are typically the first ones someone wants to sell when is distressed and have lesser sentimental value for the owner and typically have some equity (as traditional financing asks for bigger down payments to get a mortgage for vacation homes then residence)Can you share your experience buying under priced houses on vacation places (beach or ski resorts)? 

Hard credit inquires initiated by you the volume does affect the score some but not a major driver as other metrics they weigh.If your score is really low then there is usually a lot more than extra inquiries going on.To be a successful investor there has to be a life shift on how to manage and grow money with using credit.A bad use of leverage might be taking vacations, running up credit cards for toys, buying cars, etc. that have depreciating assets and do not give off a monetary return.Conversely if you do not load up on bad debt then that helps qualify  for the good debt.

Does anyone know how to find out what housing and non-discrimination regulations apply to vacation rentals vs long term rentals? 

Again in NC, if ordered to vacate the premises, they have 10 days to pay or appeal the decision.

They are producing about gross 130k on vacation rental market.  

Bought and managed properly, real estate will provide you plenty of chances to take vacations and ultimately achieve a lifestyle away from all the sane people so that you can deal with your craziness.

Cruise ship industry is making it an embarkation destination... 

Send a LEASE NONRENEWABLE Letter That gives the Tenants 30 days to vacate.

IF it doesnt get picked up on BP, let me suggest this.Advertise it in both Cleveland and Cincinnatti (bigger towns near you) on CL, as a vacation or resort land suitable for building your dream cabin.