Greetings good people! I will get right to the point: I am considering buying my first 5-series and drawn primarily to the E28... mostly out of a boyhood infatuation with a neighbor's 535i, but also because I think that there is a substantial bang-for-the-buck factor with the older models. So here is where I have some questions and need recommendations before I make a selection:

1. Are there any significant maintenance/reliability differences between the 528, 533, and 535 models?
2. What are the most common issues I should look for/ask about when buying?
3. What is the typical mileage lifespan for a reasonably well maintained specimen?
4. How well does the aftermarket support parts availability and pricing on these. i.e. am I better with an E34?
5. How well does the E28 lend itself to the weekend mechanic? decent elbow room under the hood, parts easy to get to/remove/replace, need for exotic tools, etc, etc?

Thanks!