Kitten peeing everywhere

[SecretRed]

A few week age whilst doing some gardening in our front a kitten came over to us. It looked to be about 8 weeks old and really thin. We gave him some chicken and some water and our ds let him into the house and he's been here since!
We did all we could to find his owner. Got him scanned, put posters up and notices on all local lost &found sites on fb but heard nothing. We have two adult cats already so didn't mind keeping hold of him as he seems to have been abandoned.
He uses a litter tray no problem but he also likes to pee in other places. Kitchen floor, my shoes, corner of my dining room and I've just caught him peeing on my drainer which was the final straw.
Is there anything we can do to stop this? We've kind of reluctantly said we'll keep him but it won't work if this keeps happening. We've got full time jobs, dc's and 2 cats already and can't cope with a stinky unhygienic cat pee house on top of this!
Thanks.

[NRose92]

If the cat is 8 weeks old shouldn't really be giving him/her chicken.. ild stick to dry biscuits and water, the only thing I can suggest with use both working full time is keeping him in one room with the little tray food and water, one of my kittens wouldn't go in the litter tray if it was dirty which was a total nightmare

[SecretRed]

It was obviously hungry and it was all we had as didn't think adult cat food would be suitable. He's been here 3 1/2 weeks and has proper food suitable for him now.
Litter tray is clean. My other cats don't use it as they go out.
I will try confining him to one room. Feel a bit mean though as he's had the run of the house so far!

[NRose92]

He'll just be very hyper they are at that age, he could of been through a traumatic start before you found him.
Wherever he has previously pee'd his scent will be on it and he'll think it's ok to pee there

[junecat]

Try a second tray too, mine won't poop & pee in the same box x