For building finishes, I use Scalescenes https://scalescenes.com/ . Both OO and N gauge covered.
They have a few freebies, so you can have a go without any cost!
I have bought and built a few of the buildings and they are both good value and give very realistic results with minimal input - instructions are good, however it is important to get the card thickness right. For the heavy card, I get mounting board from the local craft shop (c. €10) for an A1 sheet, however it does go a long way.
I get good use from the "Scratchbuilders yard", as they provide, brick, stone, timber finishes, roof tiles, etc which are good value and you can print off as many times as you like.
Brief note - use an inkjet printer rather that laser, as the quality of print is generally better.
To add to the comments a great piece of art and hopefully you are proud of it - I know I would be ! Certainly catches the urban feel to a "T" and I am sure the boys at IRM like the ballast and bubbles ...
Certainly watch in awe and with interest.
Thanks DV, that's interesting. I've seen that video clip before but wasn't sure how reliable it might have been due to wear or chaffing on the fine thread. Do you know if it still working well for your friend on the BR 2-6-4T loco?