Did I get a fair offer?
According to the website, I would interpret that the Glasoase is an uninsulated winter garden and Terazza is just a roof?
Weinor Glasoase ® Terrazza L Originale
Your statement contradicts itself there.
Otherwise, what also affects the price is whether you have 3.5m long glass roofs or with a central bar. You can't lift 3.5m anymore with just two people and therefore need more people and possibly different transport options.
Is the awning an on-roof or under-roof installation? Electrified/automated, etc.
We also had an offer from Weinor 4-5 years ago. Looking at the pictures, probably the Terazza plus with the overhang and the recessed gutter. We would have ended up at 6x4m with awning and vertical awning at 20k. That, of course, is hardly comparable with the current price increases. We then decided on a somewhat cheaper provider. I believe Weinor is already operating in the higher price segment.