In an attempt to try to bring this thread back to what I believe was the original topic, how does the (still proposed, I think) Part-M Light factor into this?
BTW, I believe this post by @mh is also relevant if discussing owner maintenance, which Jan might be asking about (“very personal own maintenance shop”).
Sebastian_G wrote:
As you write for N-reg things are easier because at least you only require a personal A&P qualification so you can work on your own without the overhead of an organisation. But also for a pilot/owner with another job this would be tremendous effort.
I find that maintaining each plane is about the same effort as maintaining an older car that’s used on weekends. Planes are often simpler than cars, but obviously on a plane you can’t let anything go too long. I maintain my two aircraft as you describe, plus one such car and eight such motorcycles, all ready for use. That’s a pretty big effort, more than I should probably take on! At some point I may sell one plane to reduce the work load.
Re the FAA A&P and IA certificate requirements, often in practice for every guy that has an A&P there are more maintaining their aircraft under his direct supervision. That is fine as long as it is done within the rules. The experience requirement to get an A&P is often earned while working in a primary job, then the primary job changes but the A&P certificate and enthusiasm for aircraft remains. I work with one general A&P, one A&P who does primarily electrical work, plus an inspector (A&P IA), none of whom have worked on aircraft for a living in years.
My personal maintenance shop is my hangar, occupied sporadically by people I need to be inside. As Peter so often points out, correctly, its really the hangar that allows you to maintain the plane. I think everything else can be managed in some way regardless of the regulatory regime.
Sebastian_G wrote:
The best approach is to team up with a local maintenance shop, do the labour intensive work yourself under their supervision and pay them for the inspections, paperwork etc. Also much work with old airplanes is diagnosing problems, chasing down parts etc. and that usually does not even require any formal maintenance qualification but lots of dedication…
This I agree with, and also with ‘teaming up’ whether its with a shop or an individual mechanic (for N-register) . I’m doing an annual inspection over the next couple of weeks and taking the opportunity to replace a bunch of old oil and fuel hoses. It’s quite a bit of effort to figure out each individual hose, assuming you want to reuse the very expensive fittings where possible.
This year will be an expensive annual, likely $700 or more including a few odd jobs like the hoses and an oil change… 
Peter wrote:
I got my information from a US engine shop which does a lot of Exp work and knows the regs.
What does an engine shop know about the bulletins from each individual kit manufacturer? Not to mention what does it know about the “regs” about this in Europe? Nothing at all, that’s the answer. The bulletins are documents from the kit manufacturer to the builder/owner exclusively, and there are no "regs "involved other than the fact that they are public documents, and thus any AA or accident investigation bureau can read them.
In Norway the regulations state that the builder/owner are required to read and understand all these bulletins, and determine if they are applicable for the specific aircraft. This is more or less the case everywhere. Typically these bulletins contain fixes to unfortunate or poor design decisions, and these may already be fixed by the builder.
