At least in a group owned TB you can afford to by the maintenance manuals. The CD (includes maintenance and parts manuals, SBs etc) is supplied by EADS-SOCATA for the princely sum of 1000 Euros, oh and 400 Euros a year to keep it up to date....
We are going off at a tangent here, but the above scam is not Socata specific.
The whole GA aircraft business runs on (supposedly) regularly updated maintenance manuals. The main quasi-monopoly provider of these is an outfit called ATP, which has done "deals"
with the manufacturers under which the company gets money for allowing ATP to republish the info, and in return doesn't make it available for free. And ATP charges the users a
lot of money for the service, of the order of $1000 per CD.
For aircraft servicing, there is a presumed legal requirement to be in possession of the latest service info (this I believe is spelt out in the FARs; not sure about G-reg)
even if nothing has actually changed, which plays into the hands of ATP.
In reality a lot of service firms have the information already, on paper, on microfilm, or on CD. Often it's not current but hey who cares if nothing has changed for years? They can get the really important data (SBs and ADs) separately. Every maint firm chucks the "old" CD out every month but they aren't supposed to pass it on to anybody. In reality you can pick up the ATP CDs on Ebay and other places... they are quite freely available.
Finally, if the maint firm has never seen your aircraft type before, would you really want them to do the work???
There is no shortage of maint firms who will work on a Socata and who have the data. There is a shortage of maint firms that will do a
decent job - on any plane type - and sussing this out is one of the "joys" of ownership
Socata spares are not a problem and never will be. Most planes flying today are out of production, but all the time the spares business is viable they will be available. The spar issue was an AD which like any AD would have been done, in this case years ago. Again, every plane you look at has an AD list as long as your arm - this is aviation, after all. Some are longer than others. Socata are a long way from being the longest.
The one criticism of TBs is that while the build quality is very good (compare one close up with a Cirrus or a Diamond or a Piper/Cessna, for example) some of the internals can be hard to get to, which can add a few hours to the labour cost of connecting up a new GPS or whatever. This is the price one pays for a well designed ergonomic cockpit layout - most spamcans have a flat piece of metal in which holes were cut for the instruments, and the result looks like a control panel from the Titanic.