Fixer upper for first bike?

[peanut]

I am an avid Craigslist browser. I keep seeing these bikes that need a bit of work on there for pretty cheap. And, after a while... its tempting. I'm pretty handy around the house and I have electrical and woodworking skills. I have shyed away from working on cars though, mostly because if its not back together by Monday, I'm not getting to work! And the specialty tools... who knew there was a 5.5mm socket?

My philosphy was to buy a bike in good working order, so when something is broke I'll have some idea what it should look like after I fix it. But these bikes with leaky gaskets or electrical issues seem really tempting. Are they OK for a newbie to tackle with patience?

Thanks.