Careful with co-ops. You don't own the dirt. You own stock in a corporation. Try to get a reverse mortgage or a home improvement loan on your home in a co-op. You're much better off purchasing in a condo conversion, subdivision, planned unit development (PUD) or on a private lot/parcel.
Country Estates MHP has an option of purchasing shares in the co-op that owns the park. If a Buyer is interested in the shares, they can obtain more information, with the net result being and a lower HOA monthly fee. So, basically, you can get the 'dirt' about owning the dirt :-) I hope this is useful information.