This sounds very strange that You have those exclusivity arrangements there. Most of the buildings in Riga, Latvia has at least 2-5 physical connections to choose from (an even more providers as they could share one cable). Maybe it is because most of the buildings are soviet ones and only flats themselves ar privately owned but building itself is owned by municipality. Last mile is owned by private companies mostly but everything before that is owned by state.
I can get up to 1gbit connection for 15 EUR,
100mbit for 7 EUR because of competitive market
It easy to run cables to those buildings because they are built according the same blueprint. You can run the cables the same way, no need to create separate plans which is an extra cost. In Budapest old soviet buildings have the best internet(fiber).
We usually only have one or two competing provider per building, but their prices are still low(same as yours).
I can get up to 1gbit connection for 15 EUR, 100mbit for 7 EUR because of competitive market