Go with what is well supported in your area. Gp, Crg, Birel, Shockwave, Arrow, Margay, Intrepid all have readily available consumables and racers with knowledge to help with tuning, spares etc… Sure I missed someone, but you get the idea. Nothing worse than getting a great deal on something and needing parts or support and coming up dry.
There were several racers at Imi & The Track this weekend. Go out on a nice day and talk to the “end user’s” for a neutral view.
There are a lot of good deals on used karts right now and if you use common sense it may not be a bad way to go. You don’t want to buy used then turn around a few months into it and have to buy new.
Call Kartworks, Imi, The Track, Shockwave, Grand Jct Motor Speedway, Billett or Action karting Action Karting. Down south is Cre. Get a feel for the sport and who you feel would be good to work with. Even if you buy used, your still going to need support.
Good luck & Welcome,