Technical Design and Estimate for 1/3 mile underground run on property

Hi.  I am building a new house in a semi-rural area.  Comcast fiber runs to my gate.  My house is going to be 1/3 of a mile from the gate. I need to have cable run in a trench under the driveway to the house.  All this is in the process of being built over the next year.

I need to speak with whatever department in Comcast handles this sort of custom, expensive installation process, either doing it for a fee, or giving me the technical specs to do it myself.

I tried talking to your customer service, but they are nice but to clueless to help.

Specifically, they said well I just need to sign up for service and a new account and then it will be handled.  But this doesn't really work at all, I mean, I need an estimate of what will be many thousands of dollars for technical work, done before the house is built. Where do I begin...just signing up for an account I have to sign up to be billed for internet service and give my bank account info.  Furthermore, you cannot sign up for an account if your address is not in Comcast's system -- it is literally impossible to open a new account with an address that doesn't exist yet, but this work has to be done before the house is built because it's literally under the access road to the house, which will be built before the house.  There are many other concerns here.

Can you please help and direct me to the part of the organization that deals with complicated and expensive construction projects?

Thanks.