Contrary to popular belief, neutered males can and do spray, especially if an un-neutered male has been in and marked. Whole Queens can also spray, although not so copiously so don't immediately blame the Toms.

Citrus scents are better as cats mostly don't like them. Using an odourous product though can have repercussions as the cat comes along looking for its' calling card, sniffs, finds another scent overlying it, and so lets fly again to reinforce the point that this is their bit. I've found the 'Febreze' spring fresh quite effective as a deterrant.

Putting a bowl of food at a spraying point will sometimes help as no sensible kitty will pee on its own dinner. Note I said sensible. There are a couple. Not many, I grant you, but there are one or two sensible kitties out there. Not in my house though.

LTS