[Peter Zimmermann]

Interesting thread! As the founder/former owner of Red Line Service (in the very capable hands of Marc Bixen since 1999), I can offer that I've personally performed hundreds of PPIs. I used to discourage people in the market for a used Porsche from having the seller do the PPI, and that alone was responsible for saving many thousands of dollars for potential buyers. I have inspected 356s that were more Bondo than metal, diagnosed countless oil leaks, located faulty alternators, discovered frayed shoulder harnesses, seen incredibly poor accident damage repairs, found worn out brakes, noisy wheel bearings, low oil levels, non-functional w/washers, sunroofs, window switches, misc. lights/switches, clutch cables and clutches, along with other things including bad past workmanship. I have warned buyers about rust issues, oil consumption, shock absorber life expectancy, service/maintenance schedules, etc. I would also NEVER check the function of Targa roof panels, or Cabriolet tops because of possible liability, but would assess wind noise levels during a test drive. Leak down tests were done regularly, and were an important part of a PPI.

As time passed, and the cars grew in complexity, I realized that only so much could be done during a PPI. It all started with the possibility of broken cylinder head studs, and I had to charge extra to do a physical inspection of them by removing the rocker arm covers. Then we discovered that a 911 with a tweaked chassis could be repaired to look great, but could never be aligned correctly. A/C issues were common, and on the minds of most buyers, and each issue required an estimate and a disclaimer. More and more cars showed up that had been lowered, or had suspension bushings replaced, all of which took lengthy periods of time to explain to a buyer. Then we learned that a curious dent near the bottom of a rear shock could mean that that car had been rear-ended in a collision.

By the time I sold Red Line to Marc I was happy to get the PPI monkey off my back, because Marc taking over pretty much happened about the time the water-cooled 911s showed up. If it was my decision to make, I would still do PPIs, but only on 1989 and earlier Porsches. Marc would have to deal with the stress of a very steep learning curve.

I mentioned disclaimers. Many, many PPIs had one, or two, or more. Sometimes we had no way to tell how much it would cost to repair/improve 2nd gear shifting, or if a valve adjustment would cure the ticking engine, or if barrier hoses would fix the A/C, or if brake hoses would fix the 'brakes pull to the right' symptom. Everything I found was recorded on an invoice, and each problem was accompanied by a disclaimer. PPIs; sometimes a nasty business, but always a feeling of satisfaction upon completion.