1. Get the logbooks before you sign anything
Send the listing and logbooks to your inspector first. Missing logs, long gaps, unexplained repairs and damage history show up in the records before you ever see the airplane. I do this preliminary review free, usually on the phone the same day.
2. A recent annual is not a pre-buy
The annual was done for the seller, often by the owner’s longtime mechanic. It answers whether the airplane was airworthy that day, not whether it’s the right airplane for you at that price. A pre-buy works only for you.
3. Check for unapproved parts and paperwork gaps
On one Cessna 172 pre-buy, I found a Chinese-made automotive voltage regulator. It’s not an FAA-approved part, so the airplane wasn’t airworthy. Look for a current AD compliance list, Form 337s for major repairs and alterations, and paperwork for every installed item.
4. Don’t judge an engine by compression alone
One good compression reading doesn’t tell the whole story. A borescope inspection of every cylinder, a cut-open oil filter, and how long the engine has sat all matter. I’ve found burned exhaust valves on engines with acceptable compression.
5. Run the engines and look for leaks
Some leaks only show with the engine running. On two different Cessna 421C pre-buys, I caught a leaking fuel control and a failed fuel pump seal this way. Both were dry with the engines shut down. Watch the videos →
6. Fly the airplane
Some problems only show up at full power in the air. On a Turbo 210 pre-buy, takeoff fuel flow was 28.6 GPH, 2.1 GPH below the minimum in Continental’s published fuel-flow table (M-0 Standard Practice Maintenance Manual, formerly SID 97-3G), and the airplane had reduced power and high temperatures on climb-out. A ground-only inspection would have missed it. Your inspector should be a mechanic who is also an experienced pilot. See the finding →
7. Use an independent inspector, and attend if you can
Choose someone with no ties to the seller. If you can be there, you’ll learn more about the airplane in two days than in two months of ownership.
8. Use the findings to negotiate
A detailed report with photos and repair estimates gives you facts to bring to the seller: fix it, lower the price, or walk away. Buyers have used my findings to take tens of thousands of dollars off the purchase price.