In-house software repository

My apologies if this has been covered before, but I could not find anything about it. Also, I have not seen anything about this on the internet in general.

I help friends and family with their computers from time to time. And part of that is installing and updating software. For this, I really miss my fast line in Norway! I now live in Brazil with a very slow radiolink.

I am looking for a software that would allow me to keep a repository of software on my local server so I never have to download it when I need it. This way I could have a computer installed with a minimum of effort. I have a small list of programs I like to put on a new PC that I set up and I wish there was a way to at any time have the latest stabel version locally on my server without having to download it manually.

Any ideas? I know that it should be possible to set up a repository locally for Linux and add it to the list. But any ideas for Windows?