Late to the party, but I would recommend a few things for the OP.

I use SyncBack (free version) to keep my files backed up to my home NAS. I have it scheduled to run on Sunday mornings (when I'm usually home and laptop is on the dock). The nice thing is, it does a file comparison before it starts the upload, so that it doesn't waste bandwidth replacing things that haven't changed. You can also select which folders you want to sync. Theoretically, I could also run this over a VPN connection, but I don't like to waste the bandwidth/time and weekly backups are enough for me.

The second thing I would recommend is setting up a VPN to your home. That's the best (and safest) way to maintain connectivity to your network and files at home. Depending on your router, it may have VPN services builtin...if not, you could buy one that supports VPN, or see if you can rip DD-WRT or tomato to your router (which has VPN support).

Total investment for above: $0

If you go with Dropbox, Google Drive, etc., make sure you review their privacy policies. If you have an expectation of privacy, it will probably scare you off.