I had house piggies when I was a child (free range when we had all sows). When I had a boar and sows (I didn't buy a boar, he was sold as a girl, so we got piglets) - he lived in the front room, the girls in the back room. Had to have a very sophisticated door open-don't let the pigs out- regime 
They do chew (but so do rabbits) - wires, carpet, books, shoe laces. And pooh everywhere.But you can litter train a rabbit.
Then my dad did an enclosure under the stairs when we had just the sows (2 were pink eyed so didn't mind the dullness) it was a big understair. (We had 4 girls by then).
They had an outdoor cage as well.
Lots of GP owners on here have C&C cages- made up of grids so you can adapt them. Make different levels, change shape , add on. Easy to clean and airy.
Some are inside 100%, some out some mixed.
My present GPs live out in Spring/Summer/Autumn (at night in their Pighouse which is my DC old wooden playhouse so roomy and safe).
In winter they are in at night, out during the day.
I saw some rescue that had neutered boars and IIRC they charged £40-£50. Neutering costs £ 45-£80 depending on vet.
I'd imagine rabbits are more due to size and females more as more complex.
I feel a bit
sometimes that my DD has missed the 'baby piglet' stage. But I didn't want to put money in the pocket of a petshop.
In the great scheme of things, it doesn't make a whole lot of difference.
But it made a difference to 2 little fur bundles who are now my little boys. Though they were in a rescue, being cared for, not stuck in a cardboard box.
But they've got their Fur-Ever home.
I did read on one website about a rescue guinea who used to live in a bucket . A bucket It beggars belief 