Help with a cat spraying everything

[LosingMyMindInGA]

We have a cat that is about 9 months old.  My daughter raised him from the time he was about 24 hours old.  He spent a couple of months as an outdoor cat and has been an inside cat for the last couple of months.  Recently we've been smelling cat urine through the house, especially when the AC comes on.  I finally discovered this morning what was happening.  I had 2 boxes of papers from my moms house (from when she passed away) sitting in my dining room.  My mom had cats for years.  Her last cat had to be put to sleep less than a year before she passed away.  Obviously our cat is smellign her cat on those boxes because he has been spraying them. (They were sitting next to the air return hence the overwhelming smell when the AC came on).  I've moved the boxes outside but have other items throughout my house that came from my Mom's. How can I get this cat to stop spraying?  It's a male cat and I know they love to mark their territory, having him neutered I'm sure will help but monetarily that's not an option at the moment.  So, any other suggestions before it comes down to making him an outside cat again?

[LosingMyMindInGA]

Thanks Opus.  I was afraid neutering was the only way.  Guess I need to start checking into when the next spay/neuter clinic is going to be around here.  It never even crossed my mind that he would smell the other cats because those boxes have been sitting in my dining room for a year and a half!!

[opus88]

spraying is a natural activity for an INTACT male cat.....I'm afraid the only way you will get him to stop(if it isn't to late already) is to get him fixed asap.
also you will need to use an enzyme cleaner to rid the scents of the other cats off everything plus the places he has already 'marked'
just soap and water or vinegar isn't strong enough to remove the scent from their sensitive noses....it needs the enzyme that removes.
you can get these cleaners from a good pet store such as petco or petsmart.
-urine erase, anti-icky-poo, etc.
it will take a neutering and a very thorough cleaning....it is very hard to retrain a male after they have begun, but good luck I sure hope he doesn't have to become an outdoors kitty again.-)