The time the process takes varies from state to state but generally, three months behind on your mortgage and the lender sends it to an attorney etc. Usually you get served with a lawsuit, have 30 days to respond, if no response, a sale is set, sale takes place and the lender bids the amount owed plus fees and costs, if no one bids higher and takes it the lender gets it by way of judgment, then in 10 days a certificate of title is issued if you have not paid the judgment off and a sheriff puts a 24 hour notice on your door and you must be out. if you are not out, they remove all of your belongs and your persons and place it on the curb, locks are changed etc etc.
The amount of time in days varies but the process is pretty much the same.