az350x,
Everyone's needs and wants are different. That said, my suggestion is to skip the electric coffee maker if that is your only big load. Maybe later you will want to run other things (like T.V. and/or microwave), and you can design and build the appropriate system then.
If you have some small devices to power, just get a low cost inverter that plugs into a 12 Volt convenience (i.e.; cigarette lighter) outlet. I would choose a pure sine inverter, but it isn't necessary.
If you don't have hookups, generator, or other means of recharging your batteries, and you want to extend your camping time, look for ways to reduce the draw from your batteries. Simply by installing LED lights can reduce this draw by ~30% (more in the summer).
Hope this helps,
Steve