Glad you had fun at OVRP. It’s our home track and a great place. Rotax is where it’s at if you want good size fields to race. No engine package is perfect, but Rotax motors are tanks and very reliable. That said, this is a tricky time to get into Rotax, especially on a limited budget. There are a lot of changes to the engine package for this year. That’s what EVO is; it’s a new carb, coil/e-box, exhaust manifold and wiring harness. The changes improve the performance to the point that you won’t be competitive without them. Also, for 2016, cylinders manufactured before 2011 will not be allowed, so if you look for a used motor, it would be wise to find one with a newer cylinder (2011 and newer cylinders are denoted by a two letter code stamped on the intake side of the cylinder, pre-2011 have a number stamped there). Vintages don’t need to match, in fact the best Rotax motors are a hodge-podge of different parts from different motors. It’s not hard to find decent used motors, but look for one sold bare without a carb or coil; there is no reason to pay for the older stuff when you will need the Evo parts anyway. You can expect to pay around $1,000 to $1,500 for a decent bare motor and another $1,000 or so for the Evo parts. I can’t see it being done for less than that.
The guys at OVRP are super helpful and know a ton. Just speak with Tim, Peter, or Chris and they will get you headed in the right direction.