Oh I am the queen of this. Basically spent 2019 building as much storage and usability into my tiny house as possible.
I have:
3 x reusable coffee cups in different sizes. One for my car, one for work, and the other for my handbag. Obviously, they get moved around with use.
2 x Chillys bottles. One on my work desk, one in my handbag/car.
A bottle of nice sugar free cordial/squash at my desk in work. I drink so much more water when I add a flavour.
Spare charger for my work laptop so that I didn’t have to crawl under my work desk to plug that charger out every time I needed to bring the laptop home. Also bought a wireless USB keyboard and mouse for at home so o have everything set up and just need to add the laptop!
Generally keep chargers everywhere.
The pound shop near work sells 3 cards for £1. I bulk buy so always have loads of birthday and thank you cards, plus a few new house, new baby, wedding etc. to hand.
I keep a booklet of stamps in my wallet (this was the moment I realised I was a grown-up) and another in my gift drawer.
I have a gift drawer. It has changed my life. In it I keep the cards and stamps mentioned above, but also any lovely gift items I can use during the year. For example, I got loads through various Jo Malone promotions throughout the years so I keep them as gifts for friends and family. I also add any gift bags I receive so they can be reused.
I have pretty much everything set-up with Alexa. All lights are on sequences throughout the day. Especially useful at Christmas to avoid having to crouch beneath the tree to reach the switch!
Robot vacuum with mop.
Cordless Dyson vacuum.
Automatic pet feeders. They have three chambers so I’m only filling one bowl for each pet every morning and they get a third of it at set times throughout the day.
I usually don’t do online grocery shopping but, once a month or so, I’ll do an online shop for heavy/bulky things and get it all delivered. Toilet paper, pet food and litter, washing powder etc.
Magnetic torch stuck to the side of the fridge. I will always be able to navigate my way to the fridge, even without power.
A little LED light key ring on my keys. Great for helping to find the lock on a dark night, or for poking in a deep handbag.
Bag in the boot of the car with bottled water, cereal bars, hi-viz vests, mac in a sac, big fleece blanket, spare dog bowl, spare dog collar and lead, torch, first aid kit.
Also keep flashing triangle in the boot.
I’ve bought a few items that just made my life nicer-
Expensive leather gloves. I make sure I’m not careless with them so haven’t lost them.
A Bluetooth wooly hat. Great for listening to music on cold beach walks.
A lovely round tray with a high ridge around the outside, and a flocked non-slip base. Brilliant for sitting drinks on on the couch!
A long gas lighter like the ones for lighting gas ovens- I use it for candles so I never have to remember matches.
Other than that, I invested hugely last year in just getting as much storage built as possible. It just makes life so much easier when you have room for things and to bulk buy.