I picked up a spare Combiplan kit for 45 euros last week - To my mind, a single tank for daylight processing is a pain in the backside. The holders can be fiddly to load, the tank takes an age to fill & empty, and they invariably leak. You also need around 1.2l of chemistry to fill the tank. That said, if you get the hang of loading the holder (don't used the guides, they scratch the film) and use them as a dip & dunk line, they are great. But this only really makes sense if you have a significant number of films to process in one batch (or over the course of a few weeks).

For low volume - Say 4-6 sheets per week - A Paterson Orbital is much more economical and quicker to use. I typically mix 150-300ml of developer (one shot) per run of up to four sheets. Orbitals also fetch silly money on ebay

The low cost alternative to Combiplan or Paterson is a "slosher" - But these only work if your darkroom is really dark and you don't mind working with the lights out.