Your friend is, unfortunately, WRONG. Male cats will almost always begin to spray if they're not neutered, it's just their hormones at work. I'm kind of surprised it took him three years to start up.
Get your boy neutered and you'll probably see a speedy end to his spraying. If not, a product like Feliway might be needed, but it's inexpensive and easy to use (see
www.feliway.com).
A neuter operation is pretty cheap, but if you're strapped for cash, your local Humane Society or SPCA probably offers cut-price operations.
Anyway he was still a kitten when I had him neutered, but he never did spray again. He's done some unauthorized peeing a couple of times, but that was behavioral - I brought in a newly adopted sister, and he was angry... and letting her know it was HIS territory. But after a couple days he got over that and no more unauthorized peeing.
