What if you want to sell the house

I’ve not read the contract yet. Considering they include removal an reinstallation labor for free if someone renovates their roof, they theoretically might as well relocate them to another house when moving within their service area (which is constrained as well by the region of the green certificates).

What happens when you want to exit the contract within the 30 years?

Certainly you can buy the gear. Price per panel as they age is something like this:

• years 0-5: €850
• years 5-10: €750
• years 10-15: €650
• …
• year 30: €0

If you want to exit the contract and return the panels, I have no idea. But since these prices seem to be heavily inflated to cover their labor, I imagine it’s quite uninteresting to return the panels.

When the sun is shining at peak brightness, what’s the guarantee that you get to use all of it?

All the boxes have LCDs. The 1st box shows the power generation. Then another box shows what of that you are consuming. I assume the original electric meter is still installed, in which case it might be possible to check the math.