Hiiiiiya there! (explanations of my absence later on if someone asks)
You have a lot of buyer´s experiences on top of this texts. All of them really good. I´m kind of acting as a broker right now (the reason of the absence, even if nobody asked) and the only thing to... not to add, because it has been said, but to re-write: Before you do the pre-purchase inspection, do the pre-pre-purchase inspection, and then again, a just-before-you-pay-inspection!
Just came back from London where I´ve been inspecting an Arrow IV and heading to Paris in a few hours to inspect a Robin Hr-100/250. What did I do? Getting the book is a needed step, but you need to have an idea of the daily and actual market by tracking the model you are interested in; on the net, magazines, fields out there... you´ll see times, dates, equipment and prices. Then you can see those that go fast, and those that stay advertised forever. One thing is the book value and another one the actual prices

I say this because of the Hr-100/250´s Those things cruise at 158 Kts, stay up there for 8 hours and can carry an elephant if needed,
but they are not the "famous Hollywood actress", but the "damn good theatre actor", not so known, one thousand times cheaper, but acting one million times better. I could say it´s too late to say this once you look decided to get a M-7 for yourself, but what the hell, you didn´t buy it yet!!
So, after deciding what was the stuff to find in a plane for me (I mean, the customer), I searched for the models meeting those needs. Once they are there (famous actresses and theatre actors included), I made that average pricing research. Unless there´s a really good/cheap Arrow IV to look at, I won´t bother asking about her. If it appears, then yes, have the seller sending you those books. Usually, they have a list where you can read what has been done and when (hours and dates). Ask for it to make a first selection. Those that remain "alive" are now your candidates. Ask their sellers to send as much info as they can!! The actual logs, sheets reflecting everything with the proper FAA/engineer stamps. These are easy to find if the plane had a good and organized maintenance, so if the seller says something like "that´s a hell of a work. Come here to see the plane, you´ll be pleased", just pass. The Arrow for instance. I got those sheets from the seller in a couple of hours, since day one up to the last one in June plues the last ton of pages from the books. How can it be? It was always well cared, and every single and little visit to the work shop deserved a stamped sheet stapled in the logs. Those sheets are easy to see even with the book closed, arent´they? Sending them to someone asking is as easy as opening the book on the larger pages and scanning. Easy huh? How can that be a hell of a work? Only if they don´t exist or if they are lost.
That was the pre-pre-purchase. Then, grab your mechanic, have the engineer having a chat with both of you in front of his saint manuals, have him adding his personal recommendations based on personal and read experience on the model and go visiting the seller. Best place to look at it is a work shop, no doubt. Have the mechanic and/or engineer working on it in the past helping. They should know the plane. Look at his face, look at the points he omits... He´s just helping, grabbing the prop for a compression test, not actually performing it, but it´s good in many ways having him around. Make that pre-purchase inspection.
Then the just-before-you-pay-inspection. As you didn´t sign anything yet, keep reading documents, keep investigating about the model, about the unit´s real life (spotters can be a fine resource of information here), the instruments it has and someone else´s experience with them, someone who rented it five years ago, someone who rented it last week... make a last check of everythig just before you go signing. Grab its books again, check out its numbers today, check if the tires are "the same", if that "corrected oil leak" is actualy corrected...
Whatever, I need a coffee.
Jose