I would get some outside advice from a local professional that specializes in land.

You can also search NARPM.org for the RMP (Residential Management Professional) and MPM (Master Property Manager) certified.You might consider Niche or Specialized Housing like student housing.

Scott The Book on Flipping Houses, The Book on Estimating ReHab Costs http://www.biggerpockets.com/flippingbookYou might consider Niche or Specialized Housing like student housing.

Scott The Book on Flipping Houses, The Book on Estimating ReHab Costs http://www.biggerpockets.com/flippingbookYou might consider Niche or Specialized Housing like student housing.

I use the MLS, I also have a network of wholesalers who often have some really good deals.The company I work for specializes in REI.

I suppose you know what the balloon payment is now, however most residential loans are NOT assumable and I read the ad as the seller selling as a "Subject-To" transaction as an all inclusive deed is a type of special warranty deed where the seller does not give clear title, title is subject to paying off the existing lien as agreed.

Is the subject property something really special?

Provide any references you think are helpful.....accountants, attorney's who specialize in real estate, local places to purchase materials, where to get discounts, etc. 

What makes mobile home park special (compared to apartment and houses).3.

its a pretty typical REO Transaction, I was a Listing Broker for Fannie for years, the process has changed a bit, but the basics have not, dont send them an offer of 50% of list an expect them to accept, just not gona happen (in most cases) the closing can be slow, but most REO's are, and be sure the title company gets a special assessment letter, its often missed.