On average how much does a new axle cost... then with install?

Axles arent that hard to install, I've done mine myself so I can't help you there, but if you want a rebuilt axle (just as good as new) go to autozone.com and they will give you a price for the whole assembly (most parts stores are close in price). If you want a honda one, just call the dealership and ask, they should be able to tell you.