That'd be starting with your typical mild wheeling toyota.
The $$$ is in the details for a comp level ftoy.
Stock housings bend, you can get away with them but really they need to be upgraded or you'll be changing them out every second event.
You need at least one ARB, you need sticky tires, you need the gearing, you need Longfields, upgraded steering studs, or knuckles, 2" bore hydro assist, upgraded steering pump, rear chromoly shafts, Decent seats, full harnesses, proper fuel cell, with the ball valves, suck down winches, sticky tires (and 17" wheels), dual cases with upgrade outputs and gearing for the rear case, and I'm sure there is a lot of stuff I'm leaving out.
For trail wheeling yeah you could probably just stick a chassis on top of your trail rig and call it good enough and just scrape it together with junkyard parts keeping it under $5000.
Like I said earlier its all in what you want to end up with.
