I do not buy new as you lose 20% as soon as you drive off the lot. They make it easy to lose money by offering cheap financing etc. I only buy with cash, if I cant afford I cant have it, and it does take us a bit longer to find what we want, however, we save a lot of money that way. We don't need the latest and greatest, just what fits our needs. That being said if I win the lottery where money doesn't matter to me, I would walk in and buy a custom Prevost bus........
If your fearful as you may not have the experience bring someone who does with you once you found a rig that you like. Dont pay for anything until all systems are fired up and tested to your satisfaction.