^^ I believe once the bank has the title, the mortgagor (original owner) is out of the picture. however even on a bank owned property there could still be outstanding things like homeowners fees and things that may need to be paid before closing, even mechanics liens (which are placed by the contractors if they are not paid and are legally binding on the property, secondary to the bank). These could be due at closing too. The title insurance company will check the title before insuring it, but it is a good idea to go over any possible clouds on the title with the realtor as well.
Mechanics liens are public record, but outstanding homeowners fees and things like road maintenance fees, or even assessments for things like water mains and such can be hanging there if the owner has had to walk away from the property, KWIM. You want to make sure you dont have any surprises when it is time to come up with cash at closing.
Usually these things are disclosed, and anything that "attaches" to the title/deed to the property is public record...such as secondary mortgages or mechanics liens. The title company will search this before insuring the title, so its not like you have to do it, but you should educate yourself on what is possibly out there.
Homeowners fees may not be attached to the deed, so you need to make sure the bank, as owner of the property, isnt holding on to a bill for such fees that you are supposed to pay on closing --- you dont want to get title, keys and a bill for road maintenance, KWIM. That happens where I live sometimes because there are some private road/utility services for some developments.
NONE of these things are dealbreakers, they are just things to be aware of. Your realtor wants a clean, hassle free escrow as much as you do, so h/she is likely to be aware of any stumbling blocks that could slow things down. but you need to be sure, too, KWIM.
Lets say the homeowner walked away from the property owing the bank and the community association as well. Well, the community association is going to want to be paid back fees on the property, and you dont want to get a letter from them as soon as the home is conveyed to you (which is public record). You want everything handled and to your satisfacation.
Just have a sit down with the realtor, maybe after doing some googling so you are aware of the different foreclosure types and the process.