Smallest folding bike suggestions

I am currently doing some research into small folding bikes and it is surprisingly difficult to find comparisons online. Reviews are not that great and it seems the folding bike world has Brompton-mania.

My location

I live in Berlin. Traveling with train and bike would reduce my current commute time from 45 minutes to 25 and I also use car-sharing, often end up picking up friends to drop them off home and being able to go somewhere on the bike and return with a car would help reduce my costs even further. My apartment is tiny, bikes get stolen from the inner courtyard... so... I want to get a portable bicycle that I can just take with me.

Size

I am 192cm tall though. I tried a Tern Eclipse and the rid comfort was incredible for a folding bike, but it does not fold into a compact backpack-sized bundle. It Is cumbersome to carry up stairs to the train. I also tried a Brompton and even though comfort is reduced, it is still decent even with 16" wheels.

Price

I am currently deciding between the Tern BYB with 20" wheels for 1899EUR, the Brompton C Line for 1550EUR and a Dahon Curl i4 for 1080EUR. I don't see much difference between the Brompton and the Dahon, so I am leaning towards Dahon because of the price. There is a new one coming out this year with disc brakes though... I may wait for that if the price is within the range I listed above...

Comparisons

Any other folding-bike commuters out there? How the quality of Dahon? Brompton? I am actually surprised how small the folding bike review world is. The Dahon Curl and Tern BYB don't really seem to be on the map for most and the Brompton seems to be the only bike that has long-term reviews from real commuters... I am also willing to buy a used Brompton, but they do not seem to get much cheaper used... I found an older model for 900EUR though.

Thoughts?