Oyster cards go in the back of the phone case. There are around 1000 phones with Oyster tucked into the back of the cases in every Secondary in London. If the charger is downstairs/with you overnight (which I recommend), you can make sure it made its way back in there for the morning.
Back of door for bag, coat, blazer.
Small desk with comfortable chair helps, good lighting/lamp is useful.
Second set of all equipment (pens, pencils, etc) for when they're lost each week kept with you.
Big tub with lid for books, paper, letters from school, everything to be dumped in there - when he says there isn't any homework, you'll be able to check the tub for the non-existent History homework that'll be at the bottom.
Linen bin for aiming in the general direction of uniform.
And have five sets of shirts, three jumpers, three sets of trousers by Sunday night each week. You don't want him wearing the same shirt two days in a row, not when puberty is rapidly approaching - get him in the habit of needing clean stuff every day. Two ties would be a plan as well - keep the spare with the spare pens and things with you or it'll disappear by September 22nd, never to be seen again.
You keeping the spares and then insisting that they come back again as soon as the task is done keeps him on task and trains him to not leave a classroom with the teacher's supplies bought with their own money.
PE bag is replenished with clean kit immediately so there isn't a pair of greying football socks rapidly decomposing with what may have once been a banana in the bottom.
And if he's in the habit of using deodorant, make it a neutral smelling one. We don't need to breathe in that amount of Lynx every day. We really, really don't.