Actually, there are 3 lower cost options: from more expensive to least is 1.EAS Kicker 2. EAS Buddy (from RSWSolutions) and 3. the open-source sw (also RSW or from Souceforge.net).
The disadvantage to the sw is that you need a laptop whereas the kicker and the Buddy can be carried in the glovebox and used virtually anywhere. The difference between the Kicker and the Buddy is that the Kicker has a display and will give fault codes wheras the Buddy only clears hard faults so you're not locked on the bumpstops.
The open-source sw will give all the functionality a Testbook/Rovacom(Faultmate)/Autologic would for the EAS system: reading and clearing faults, forcing mode changes, and stteing heights (calibration). All you really need is an old serial cable and a couple of small spade connectors if you're careful and can read instructions - though getting a GBP3.50 OBD connector is not unwise.
I tend to agree with Irishrover's advice above. If I had to do it again, I'd download the EAS sw and make a cable for nought - and save for a Faultmate so that I could deal with the rest of the silly electronics.
BTW, very good info for dealing w/all sorts of RR probs on rangerovers.net (in case someone does not yet know)