Small space composting

I live in an urban home with a small garden, extremely small compared to the standards i see in most posts and blogs, websites, etc.
I have been composting as much as possible but i can't get even close to composting enough for my needs with my space. Every year i am buying in compost to grow what i need to grow.
I also have a very low budget so i don't top up my beds as i would like to, i usually only fill a hole where i am about to plant in to. The rest of the slack is picked up with fertilizers, both bought and home made.

Can anybody share pointers on how to create the most compost possible in a small space? Ideally i would love a closed loop system, but i think i will need animals for that. I plan to get ducks soon if all goes well, but that is all i have space for. I also plan to try humanure soon, if i can do that without modifying my toilet, as it is not my house.
I don't create much kitchen waste either, as i hate to waste food! i even eat my apple cores, minus the seeds

Am i doomed to buy in compost every year?

Any tips would be appreciated. Thank you all <3

Every bed is a place to compost.
I layer leaves onto my beds in the fall, pour pee onto the leaves over the winter and move the remaining material to a compost pile in the spring.
This adds nutrients directly to the place you want them to be anyway.

I've recently started using totes filled with leaves to put 5-6 nursery pots in.
This serves multiple purposes.
The leaves hold water like a sponge, providing it for the the plants on the pots, without drowning them.
At the same time the leaves decay, becoming leaf mold.

Something I've yet to try is a bucket stepstone.
Basically a bottomless bucket, sunk into the ground and covered with a stepping stone.

Chop and drop directly onto the beds works well for small spaces too. Instead of hauling everything to a pile, just chop up any plant waste and leave it on the surface. Worms pull it down over time and it feeds the soil where you actually need it.