@Corky441 as promised we did do the ATV excursion through Carabali. There was another for Camp Rico as well but I cannot speak to that.
As for the machines used they were in rough shape. In fact mine would not go into 4x4 and I got stuck in the mud on one of the trails which was actually the most fun part. If you're the type who wants new, pristine, carefully maintained equipment this would not be a tour for you. The stops were beautiful and we took a dip in a very lovely, clear river. Painted ourselves with rocks and minerals, and then got shots at the bar after.
There is a shuttle/bus that takes you from the port to the venue and its about a 30-40 minute ride. The bus had AC and was comfortable also taking us back to port after the excursion. He makes two stops on the way back one near a shopping area close to port and one back to port directly.
It was a blast but don't go expecting nothing to go wrong. As I said I did get stuck for a bit until I was pushed out, and another ATV decided it didn't want to go into gear after a stop. Quick fix but my group is generally mechanically inclined and unphased by the odd breakdown in the jungle.
If things like that concern you however I'd choose another excursion. All in all I would do it again without hesitation. It says long pants required but they are more of a suggestion. It does get hot by your legs and you can burn yourself if you're not careful in shorts. They will turn you away if you don't have closed toed shoes and your drivers license.
As for the deposit I didn't pay attention. Upon check-in they took my drivers license and a credit card and sent me on my way to pet the cats. Did I mention there were cats? About six of the friendliest little barn cats. I would've paid the money just to pet them all day. On my current credit card statement I have no charges from Carabali so if there was a hold it fell off quickly.