Hiring a contractor - why I screwed myself

I had a contractor out last week familiar with old house restoration come look at the farmhouse.  He had a multi-page article in our local magazine in his restoration of a century old craftsman, so would understand how to fix all the funkies in my old house.... keeping its integrity without Home Depotizing it. 
This is how in the last four years I have screwed myself.  By doing (what seems like) four years of research and how-to classes and online information and books, by hiring my own labor when things get over my head (sometimes it doesn't take much!), by shopping craigslist and all the re-use stores... well, that basically makes me a cheapskate.  Since I can find most anything I need dirt cheap, I can't see paying someone $8K to replace the siding on my leaking exterior wall (and weatherproof, and seal, and replace windows).  One wall.  One wall of six.  Because I know with a bit of hunting I could find leftover cedar siding from someone's project for a couple hundred. I could get those windows for $700.   And if I had the experience to be able to know and explain how to fix whatever weirdness (mold? rot?) is under that siding... I could have Javier do it for $300. 
See the knowledgable contractor knows what to do.  I don't.  But it is not worth the $7K difference for me to hire him.  And that is why I screwed myself.  I can't get someone in who really knows his old house stuff because I know I can do it less expensively.  I already figured out if This Old House was going to re-do my house, I wouldn't want them, since I watch what they put in and think "Holy crap, they paid full retail for that gas stove/old barnwood flooring, patio flagstone, etc etc. that they could have got for 1/5 price on craigslist?"  Cheap. Skate. 
I still haven't had that architect out that I won at Wilder's school auction.  At least I don't have to fret about that money!