Best age to neuter, need opinions!

Cider was spayed at 6 months by my roomie. She started to mark outside just after a year and is now a compulsive marker. In my house she has never had an issue but she has felt the need once in a hotel room which shocked the h*ll out of me.. and 2x at Dekka's house.. She also loves to hump..

Smudge does not hump.. but he's become a sneak marker. He likes to trundle from one human to another and along the way let it go.

So at just under three he's being snipped today. May not curb it, but it's something.

Lizzie was spayed early and marks/humps. Blaze is 2 years old, but marks too. No humping though.

Like others, I would train the behavior rather than just snip him. I personally feel it's in the best interest of the dog to have all his/her parts, so I would work on the behavior if it were me.

Kya humps (only inanimate objects), and she was spayed around 1 1/2 yrs old. She only marks outside.

Chloe marks outside, but doesn't hump, and she was done at 1 yr old.

River has to be done before he hits a year old due to his rescue's contract. I'm planning on getting him done around 10 months old. I'm tempted to get him done earlier, but only because I'm considering fostering and most groups want all resident animals fixed. I don't have any issues with him being intact currently.

I'm going to work on the behavior, but he WILL be neutered at some point as I am involved in rescue work and feel like a hypocrite if I keep unaltered animals. My two unaltered boys are due to health issues.

I think I will talk my mom into waiting til he is a year old atleast, its no hurry for me really, we dont let our dogs wander and my unaltered boys are fully supervised when out in public. I still need to get my 8 month old kitten Kevin neutered, hes my only unaltered cat, he doesnt set foot outside though so theres
No risk.