I have a few hobbies, one of them is owning a little British roadster. There are two types of Triumph owners...wrench turners and check writers.
As an ex-Spitfire owner (and someone who is both a wrench-turner and cheque-writer depending on the situation), I know exactly what you mean
Cars are actually a pretty good parallel to the arcade hobby. In both cases you have old, cranky machinery that has surface commonalities with other old, cranky machines of the same type, but each one does things in its own ways and has its own set of strengths and weaknesses as well as personality.
Getting to know those strengths and weaknesses is part and parcel of either hobby, regardless of whether you're doing your own maintenance or shopping the work out to someone else. If doing your own, you need to have at least a rough idea of what's up before turning wrenches or breaking out the soldering iron; if shopping the work out, it helps to know why you're sending it out so that you're writing cheques for the smallest possible amounts
Here's what I'd recommend: for now, look for a Tempest for sale that's in a radius you're willing to drive to pick it up. Figure out what you're willing to live with condition-wise before looking at one so that you have some idea of where you're comfortable starting your maintenance learning curve - some stuff is well within the DIY range for novices, and not worth shopping out if you can fix it yourself in an hour or two. When you look at the machine that might be The One, see if it's within that comfort zone. If it is, pull the trigger and good luck
Note that I'm saying this as someone who has bought cars and arcade games sight-unseen before, sometimes at great distances. The experiences have been good, bad, and indifferent; it's just luck of the draw. But for starting out, I really do recommend going and looking at machines in person. Just try to keep the 'shut up and take my money' instinct in check when you do
