Definitely go with at least the CPA2 or CPP2 if you want to do E6. If you will also do B&W, you might want the CPP2 because it can rapidly cool the tempering bath by introducing cold water. The CPP2 also has more accurate temperature control (digital display, +-.1C).
If you don't want to be tied to the machine for the processing cycle, move up to the ATL series. They are more expensive, so it is a time-value question. The ATL series also needs tempered water input, so you have to buy a delta or similar to provide tempered water to the machines. This adds to the expense and installation issue. The ATL 1000 series has, I believe, a solution for portable development, so you could toss it in the back of your Winnebego and process while on the road. It requires a bucket of water, into which you submerge a pump and a tempering unit.
The ATL 1000 series only does film, so if you want to do paper too, you'd have to move up to the 2000 (or older ATL-2, if memory serves).
The CPA2 and CPP2 both do paper, so unless you really want fully automatic processing, I think you'll be fine with them, especially for the volumes you expect to run through the machines.
I do very low volumes, and keep the jobo stored until I want to use it. Then I just put it on the counter next to my sink, connect the cooling water input to the faucet (water hose connector), put the output hose in the sink, fill it, plug it in and go. (Note that it takes a while to come to temperature unless you fill it with hot water to begin with, but once at temp, it stays right on it. It is very accurate in that regard).
Be sure to get it with the lift. It is an optional accessory. If you are doing E6, the lift helps you with timing accuracy, and you can't use the expert drums at all without the lift.
Regarding the motor - ask the seller for the serial number of the unit. There were several changes over the years. The Jobo site as info on these changes. If you can, get a unit with serial number >22000, they have stronger motors.
However, I have not had a problem with my older one (serial number around 14500), even with the 3004 expert drum (6 sheets of 4x5).
The jobos do a great job with all the processes. However, heed what others are saying about water in the reels. Also, make sure the drums are absolutely dry before starting your process, or water droplets hiding in places like the lid can cause streaks.