We are about to embark on a large construction project at our home. The old sidewalks and poured cement stairs (the most half assed looking junk I have ever seen.....

) will need to come out.
I don't mind getting dirty, and I don't mind hard work. Is this something I can do myself with a jack hammer? Should I rent a Bobcat with a breaker on the front?
I would be fine with finding some guys via craigslist to take this stuff out, but it seems like 100% the folks that do cement on there are are unlicensed illegals, and I'm not having folks that aren't bonded and licensed on my property operating heavy equipment.
advice?