Basically, these are lands that technically qualify as Sending sites, but that have issues such that nobody really wants to build there.

We have a site through our PMS (Streamline/BizCor) that facilitates the bookings through a site. 

To set the scene: A cost seg study breaks your property into two important categories:1250 "real" property aka the building, foundation and other long life assets.1245 property aka anything that can be accelerated such as 5, 7, or 15 year property like carpets, cabinets, or other site improvements.

Does this mean the realtor does not have exclusive rights to sell the property and the owner is probably advertising the same property on one of those by owner sites?

YES, a person CAN sell without total site cleanup from a house fire.

Check their work.You came to the right site to learn everything you need, Good Luck!

Just wanted to introduce myself and enjoying the Bigger Pockets site and forums.

I found a property on an auction site that I'd like to bid on.

Quote from @Theodore Sutton: Check out the site meetup.com and also the events page on BP for meetings up in your area to meet people like this and build relationships.

We're also starting to scour other forums for possible investments outside the traditional MLS sites, and other areas like upstate NY.