My home builder poured me a nice thick (16") concrete patio (8'x10')
which we didn't ask for or pay for. Unfortunately it's squarely in the
way of where we want to build a deck and there isn't really clearance
above it to get the deck joists in.

I'm still fighting them on trying to get it removed, but they must have
the worst customer service department imaginable. The fact that it
cracked in half while still under warranty wasn't enough to get them to
do anything.

I've called a few concrete contractors and can't even get one to give
me a quote.

It's in the back yard and I dont have the gate clearance to get a
bobcat or similar through.

As a result it's starting to look like i'll be doing this myself .
I've never done any concrete work on this kind of scale, although i've
got friends who've got some experience with jackhammers and excavation
and will work for beer. One suggested that i rent a big hammer drill
and drive a grid of holes into the slab which I could then drive a
jackhammer into and break apart... is that plausible?

How likely is it that a builder would put rebar into a non-structural
patio?

Any other advice?

Graham