Share 'Castrated male scent marking indoors'

Can anyone give me advice on stopping a castrated male Setter from scent marking indoors. Bailey is our 2nd setter but 1st male dog. He came to us 5 months ago as a 1 yr old, already castrated by his previous owners just weeks before we took him. Everything was fine to begin with (We had sort of anticipated the stealing from the kitchen bin and hoarding socks from the laundry) but suddenly Bail...