Owning a pony is just as much commitment as owning a horse.
It may not need shoes if it's going to stay on soft ground all the time but while you are out walking it unless it's hooves are in excellent condition and it's only a very short time it's on hard roads it will need them
Regardless it will still need it's hooves triming and keeping in good shape ( literally) every 4/ 6 weeks
You absolutely will need a vet , even the toughest healthiest pony will get ill from time to time.
They can't eat many different types of veg , the odd carrot / apple / thin sliced swede once a day is fine but you can not just give them a bucket of veg.
It has the potential to give them *colic which can kill .
Manure has to be well rotted before you can use it ( 2/3 months ideally) so unless you have a very big garden and are a keen gardener and understanding nighbours there is no way you will use all it's manure.
*in easy terms colic is when a horse / pony has got a blockage in its intestine this can be cause by the wrong food , the animal eating to quickly , food ( esp veg/ fruit ) been swallowed in big chunks or just sods law .
Equine can not be sick so it has to go out the other way but if that's blocked it can not.
Vets can remove the blockage if they are called out quick enough by putting there hand / arm up the animals rectum and manually scooping it out the poo and the administration of liquid paraffin via a tube down their nose and into the stomach, get this bit wrong and they will get the LP into their lungs !
If they cant get there quickly you have to do it. There are no ifs and buts about this.
Your pony will roll on the floor , kick it's own stomach and you and be very hard to handle due to the pain it's in.
The rolling on the floor can easily twist its gut and kill it very quickly, so even after the vet has been you need to walk your pony , sometimes for hrs to stop it rolling .
I have had to do all of the above and had the help of other very experienced owners and still really struggled.
Think of the worst case of stomach ache you have had and know that you could not be sick or poo.
This is just one of the things that can go wrong. . . . Do you still want a pony ?