How to conduct a wifi bridge to the private sector?

Question

Computer networks

Hey!
The question is somewhat non-standard and I still have difficulty formulating it. But, one way or another, I hope for the advice of wise readers or more or less involved in the following.
So, backstory:
A couple of years ago, my family and I moved to a private house. As it turned out, there was not a single Internet service provider in the quarter. Moreover, none of the providers was ready to connect me to the network and make me their subscriber due to "technical complexity" and "economic inexpediency".
I have been suffering for 2 years with a "home Internet center" from one of the mobile operators. The speed is limited to 25 Mbps, the proximity to the Moscow Ring Road and high load practically kill the efficiency, it is almost impossible to use the Internet during peak hours.
After a little googling, I found an acceptable solution: in direct line of sight from me (literally across the highway) there is a nine-story building, to which I decided to connect via a WIFI bridge. The equipment has been bought, my eyes are burning, it remains to choose a provider and conclude an agreement ... but, alas, almost everyone refuses to connect because I do not physically live in an apartment building. Allegedly, the cable can only be brought into the apartment (without access to the attic), and then - do what you want.
I honestly tried to negotiate with the residents of the upper floors about installing an antenna in someone's house, but the level of technical literacy and general trust in crooks from the street in our time is so low that the idea failed without a chance of implementation.
The crux of the matter is: have any of the readers been able to do something similar? If so, how did you negotiate with the provider and conclude an agreement? Are there any pitfalls? Is it possible to install equipment on the roof with the help of a provider and become a subscriber while physically being in another building?
I apologize in advance for the clumsy syllable and thank you for the answers.

Answer 1

I see two options: 1) look for a provider that immediately connects over the air (they call me once a week); 2) negotiate with someone from the tenants of the nine-story building.

Answer 2

Well, theoretically, you can drive up to the housing department or homeowners' association - depending on what's in this house, so that they let you into the attic. Well, either buy / rent an apartment in this house, or charm / bribe / intimidate the owners of some apartment ... :)

Answer 3

Officially, the provider cannot connect you, since you do not live at this address.
You can chat with the residents of the house, agree that they get a cable from a second provider for you personally. And you will pay both their provider and yours. (I agreed so myself) The cable goes to Mikrotik SXT and immediately broadcasts in my direction over an encrypted channel.
Also, judging by the description of the "home Internet center" - do you use yota?
Look at the map of base stations and choose a less loaded one. I took out the yota usb modem with a router in a hermetic box on the roof of the house and caught less loaded stations. But my situation was even worse - iota was not caught at all from home. Worked only from the roof. The router and modem lived on the roof for about 5 or 7 years (and are still alive, they just no longer needed), until Akado with gpon came to the microdistrict.