I can testify that this works well in Germany, and always has, even prior Part ML.
We regularly run engines (including their accessories), Propellers, harnesses, etc. on condition.
This includes palnes used for primary, VFR night and IFR training. Neither the CAMO nor the LBA ever had anything against that. All we did was sit down and discuss sensible means to ensure continuing airworthiness.
I am not involved in dealing with the financial side of things, the only data point I can offer is the isue of a Mode-S-address to an aircraft that did not have one, which is 25€.
Interestingly I’m on D-reg and have just received an email from my CAMO saying “Your engine will expire next month so can we book it in for overhaul” – just like that 
I don’t think so….
mmgreve wrote:
Your engine will expire next month so can we book it in for overhaul”
They might just be trying to cover themselves and are expecting you to say no … so that the ball is in your court ?
@mmgreve If your plane is not used commercially, e.g. in a charter company, and you do not use the CAMO to take care of all your maintenance planning (a.k.a Controlled Environment/ “Überwachte Umgebung”) you can use a Self-declared-maintenance program instead of the standard one written by the manufacturer, and in this you can decide that you will use certain components (e.g. engines) beyond their TBO. You have to specify the means you intend to employ for ensuring the continued airworthiness of said component.
Please also note that this program is declared by you, it does not need any kind of costly “approval” by the LBA or the local authority.
Edit: The only exception to tbe above are items listed in section 4 of the AMM. The Cirrus’ chute is a good example of this. The life limits in this section, and only in this one, are part of the aircraft’s certification by the competent authority.
