You're a burglar, BUT...

[AintNobodyHereButUsChickens]

Instead of stealing things, you do things to mildly inconvenience your victims.
What do you do?

I'd rearrange all the kitchen cupboards.

@PuffinDodger I too was thinking of Amelie! For those who have not seen it, her pranks on the mean grocer are as follows:

• Setting his alarm clock to 4am.
• Swapping toothpaste and foot cream.
• Swapping the bathroom door handles (knob on one side, lever on other: a peculiarity of French houses).
• Replacing one of his shoelaces with string.
• Putting dim bulbs in all the lamps.
• Replacing his slippers with an identical smaller pair.
• Putting salt in the whisky decanter.
• Sticking a pin through the cable of a lamp, so that it explodes when he plugs it in.
• Changing the stored phone number of his mother to the psychiatric hospital.

After she's done these things, there's an imaginary shot of her carving a Z into his front door.

I swear to god you lot - can you please stop coming to my house and messing about???

Put all their clocks and phones forward by half an hour. They won't be late but they will have to wait around in the cold for stuff and make awkward small talk

@LordProfFekkoThePenguinPhD an old friend of ours was terribly messh. She told us that one day she came out of her living room to find 2 policemen standing there. She had left her front door open and the flat looked such a state her neighbour assumed she had been broken into so called the police. She was in the living room the whole time

Paint an evil grinning face on a wall facing the bed in glow in the dark paint, so it can't be seen until the lights are switched off.

Cold porridge in toes of slippers
Rearrange the kitchen

I tidied up, did the washing up, then made sure I'd locked all the doors before going to work. H got home after his night shift and phoned me at the office to say we'd had burglars - my heart sank and colleagues could see it was bad news. I was asking what had been taken, was there any damage? Then he said "they've done the washing up". This is how colleagues discovered I'm not the world's most enthusiastic housekeeper

Steal several different socks.
Change times and temperatures on the central heating.
Stuff a screwed up piece of paper / card up the vacuum cleaner tube
Mismatch the times on any clocks.
Loosen lightbulbs.
Steal odd drill bits, screwdrivers, and the bit that comes with an electric drill.
Take all handy notepads and pens. All of these can be hidden in the Christmas decorations box.
Disconnect power from auto light gas hobs. Fires etc.
Clean temperatures and locations off cooker controls.
Blunt carving knives and hide sharpener.
Change WiFi id and password to free secure WiFi WiFi on ".........."
Connect doorbell to neighbours frequency and put sticky stuff behind their doorbell button.
Leave out squeaky toys for the dog.
Change the touch up paint in the shed / garage for similar..but not the same.
Drill many tiny holes in any 1 piece of wooden floor or furniture, and leave the sawdust.
Remove 1 spring from underside of sofa in most worn spot.

Ooh and another, take all their keys off the bunch and put the loose keys in the “random keys that no one knows what they are for” drawer/box that I’m sure everyone has (don’t they?!!)

If they've got any upturned bottles of almost empty shampoo in the bathroom - turn them back the right way up! Heh heh heh.
Hide egg timers around the house. Do a load of laundry and mix darks with whites. Loosen stitches in the bum seam of every pair of trousers.

So many evil people on here

Move their children's height charts six inches up the wall so they start panicking that their kids are shrinking instead of growing.

Leave some lion poo next to their catflap.

Change the number on their wheelie bin to a random other one (e.g. a 3 becomes an 8 or a 1 becomes a 7).

Remove all of their door handles and put them back in upside down.

Move everything that's in their fridge to their freezer and vice versa.

Leave an Ann-Summers-style bra (unlike that owned by any female members of the family - take a few different ones with you to ensure a non-match) at the back of the man's pants drawer.

Put up a card on the mantlepiece saying "Happy Birthday, Daddy, from your little Boy" if you know they only have daughters.

So many evil people on here

Worrying isn't it?!

Break all the lightbulbs.

Take duvet covers off all the duvets, soak them in water, fold and leave in a neat pile next to the wrong bed.

Move exactly 3 of everything - so switch 3 dvds round, 3 cds, move 3 books to the wrong shelf, 3 items from each cupboard go in other random cupboards. Not even for them to notice immediately what has happened so they'd be finding wrong things for months.