HI great to be here! Marking after neutering question

Thank you for letting me join you all! I have a cat, Checkers, age 4. He was neutered at age 7 months and for the last month or so, he has started marking things (he actually lifts his tail and spray comes out, and it does have an odor). He has sprayed ME several times; the walls, my daughter's mattress, and various things around the house. Although I understand it may be caused by several things, my question is HOW do I get him to stop? And how can he do that when he has been neutered? Maybe they didn't remove all of his testicles?? I'm at a loss here. He has always been a little bit emotional/neurotic at times but this?? Any suggestions?

Some male cats do continue to spray after they have been neutered. Have you tried Feliway? It may help.

But he was neutered at seven months and didn't start marking until four years old? There's got to be a trigger of some kind in this case for suddenly starting this behavior.

You didn't recently move did you? Maybe there's some residual cat urine from a previous male cat he's reacting to. Another guess is maybe somebody tracked in male cat urine from a neighborhood stray.

Has he been seen by a vet since this started happening?

He needs a vet and if he has been spraying for over a month he needs a vet fairly quickly. Sounds like he has a UTI not a fun thing for a cat or an owner.

Well we HAVE moved but this was just a week ago; he has been spraying basically for a couple of months but a lot more so in the last month. I have another male cat, which I have had since he was waaay little; he is not neutered yet but I've made his appointment to be. I see him marking outside once in awhile; I have 5 cats total, ages 7, 4, 2, 1 and 4 months, 3 males and 2 female. It MAY have started around the time the kitten came to us but I remember him doing it very randomly even a couple years ago. I HAVE noticed that his pee is a little on the brown side, a little dark; and I see him squatting to pee fairly often, so a UTI probably is a problem. I still feel that the marking may be a somewhat seperate issue though, as like I said he has had behavioral quirks since he was little (kinda moody, a bit of a bully, high strung at times, almost like he's bipolar!!!) And he purposely seeks out things to mark, as in me and my husband both. So in addition to a trip to the vet what can I do here at home to either stop him from it or get rid of the smell when he does?