well, for what its worth, I'm 29 and I've been tinkering for a few years and enjoy doing the work and saving money. Oh and I also like feeling a little challenged perhaps. and getting some tangible results, working in mol bio doesn't afford too many of those; short term at any rate. I don't know if I am considered young, but if I am by the standards here, than I can say that there are some youngsters out and about who grew up with good parents who taught them what a good work ethic is. The next generations will have slackers and folks who want to rebuild old cars and bikes and everything inbetween, way its been for some time now... personally not worried. I watch my younger brother go to work as an architech from sunup till well past sundown, and that's just on the weekends....
Problem I have is I usually have no way of knowing when its going to be a no brainer and when its going to turn into something totally different. That's when I feel old, maybe that's more of what you mean perhaps? You feel like you can go out and fix it all and then one project seems to lead to another and at some point you just want to go back to the nice cozy grey cubicle with the nice cozy grey phone and nice cozy grey desk.
Here's my example to hopefully show you we all feel that way sometimes: There was a - its a blurred drunken memory now- 18hour door bell replacment fiasco that wasn't so much fun. If someone had told me going into it, look the PO has wired to doorbell into the security system, and oh yeah also into every doorbell- oh did I forget to mention they had one doorbell in every room for some unknown @#$@$ing reason... and well I might have said to the boss, lets just pay someone else so you don't have to watch me cry.
hang in there keep wrenching and carry a cane to whack all those young whipper snappers in the knees as you pass by mumbling