I think you'll find that there is as much engineering involved in a hovercraft. For instance, the EDFs will not work well in reverse as they are not designed that way (plus reversing ESCs are expensive and you'll need two) . So your options are to either use only one fan to turn using channel mixing (i.e. so that to turn left, you'd have the right fan on full and the left fan off) or to somehow vectorise the EDFs with servos so that they can rotate 180 degrees. If you do the latter, it makes control setup more difficult. In contrast a circular vehicle with two independently driven motorised wheels either side and two caster wheels forward and aft should be easy to control using simple mixing.
Anyway, here's the one from our club: http://www.modelhover.org/node/452
Probably larger than you want, but same principle. Note you can't see it but the skirt is made from very thick/ deep pile fleece which works really well on smooth dry surfaces.
The lift fan doesn't need to be that big - for a 12 inch craft I reckon you could easily get good lift with a 4 or 5 inch prop. You should be able to use radio mixing to get the fan to come on when forward thrust is applied, though you may need to use a Y lead somewhere along the way, but it shouldn't make any difference to the choice of ESC.