I do nearly all of my own work, but the one guy I trust more than myself (Dano at Revolution in Solana Beach--aka the Derailleur Whisperer) gets $20 every time he touches my bike--more if he shows me how. He's taught me some excellent fine-tuning tips and tricks over the years--worth every penny. More, actually.
He gave me a new pair of NOS lenses for my 80's Oakley eyeshades last month. He's not only got the magic touch, he's also kind and empathetic to humans too.