I can't give any real recommendation because of currency differences.

But presuming you really want that 29'er (as opposed to other bikes that will do the job fine). Don't worry about the disc brakes. Just get anything with a frame with the rear rim brake mounts. If the bike comes with discs, keep the front one on (most important one) and swap the rear to a rim brake. Then voila, you keep the braking power and predictability of a front disc (good for heavier weight and + trailer) while staying trailer compatible.