You don't need the whole automated Jobo schmeer, but if you plan to get serious about doing color I'd suggest you invest in a "tank roller" -- one of those motorized tabletop gizmos that agitates the tank by rolling it back and forth. The advantage of this is that it makes your agitation more consistent, so your results are less variable from roll to roll.
The disadvantages are that these rollers only work with plastic tanks (stainless steel ones don't seal up tightly enough) and you'll probably need a bigger tank than a two-roller -- the tank has to be long enough to fit across the roller's "cradle."
Otherwise, you don't really need anything for temperature control other than a foam plastic picnic cooler (ultra-cheap) and a good thermometer (not so cheap, but maybe you already have one.) You fill the cooler with water at slightly above your desired processing temperature, give it an hour or so to stabilize (the foam keeps the heat from getting away), then put the mixed chemicals and tank in it and leave them for another hour or so to stabilize. Once the temperature is stabilized, it won't drop very much during the few minutes that the tank is out of the cooler for the first developer, and the rest of the steps aren't nearly as temperature-critical.
I'm not sure you really save much money this way compared to the cost of getting process-only at a lab -- but if you want to experiment with pushing, pulling, cross-processing, etc., it might be the way to go.