It depends on the location of the property. Where I live the county provides a lot of that information. You can search on the owner's name and then pull up actual closing documents (with things like the SS# blocked). You also get things like quite claims, liens against the property, changes in ownership, notices of default--anything that is public record.It's on the county clerk's site. The assessor's site also provides things like pictures and layouts of the property, its ownership history, and its taxable value. Sometimes you can get it from a title company. It depends I think what county you live in.

So for example if you were interested in purchasing your neighbor's property at a fire-sale price you could determine what's owed, if they are in trouble on the mortgage, and you could probably find the payment or interpolate it from available data.