Research, experience, trial and error - and then things change, a former good manufacturer and/or supplier no longer is or for that particular part perhaps and on the other side a former poor manufacturer and/or supplier can improve (sometimes). You are doing a fair amount of research which is good (obviously, as much as possible, better done before considering getting the vehicle) are you also encouraging or allowing your son to do so too, not one of theses dad's that pretend buys the toys for the kid(s) or still spoon feeds the kid(s) (obviously I cleaned that bit up 😀). Learning by others experiences, and mistakes, is often more efficient and saves frustration, time and money but they are remembered more when you actually go through them for yourself (until you forget). Hands-on experience is definitely needed with old and new cars, with hand not powered tools too, things like how tight so as it doesn't come loose or you break it. Now it seems even though a few screws, bolts, nuts need tightening or loosening a power just has to be used, fair enough for professional that have (hopefully) learnt what they're doing and need the speed to get on to the next job but not for DIYers and especially those that are learning and inexperienced. Time for tea.