If you just want to share non-sensitive docs set up something like dropbox, onedrive, google drive, etc... And have the docs live there.
If you want an actual VPN you can do with with your existing device. Here is the doc on how to do so:
http://www.downloads.netgear.com/files/GDC/FVS318N/QSGVPN_4Apr2012.pdf
What you're looking for is the VPN client part.
I know you're trying to do it cheap, and cheap is what you're doing with the above. A 'real' VPN solution should use a better device and a better authentication method. :)
Unless we could move the entire shared drive to cloud storage (with 100GB) it would be a major pain in the ass. The very thing I am trying to avoid is having duplicate copies, and data not consolidated in a single location. Ideally everyone would work exclusively inside the office building and connect to the one shared drive so there would never be isolated data on anyone's computer other than the server, and no one would have to email documents back and forth, everything would just be accessible to everyone at all times regardless of location.
When I last checked into using cloud based storage in place of a local server it was cost prohibitive and promptly shot down by the bosses. As wicked awesome as it would be, I kind of agree it's not the best move financially.
I'll check into the pdf you posted and see if I can get it configured.
Is there a reason the archived data would need to be accessible outside?
At any rate I wouldn't use cloud storage to replace a drive. I use it to augment a network share. Most products allow you to sync folders between computers. So you would set up a cloud client on the network server, and tell it which files(folders) to sync. Then every person that needs to use that data remotely installs the client and syncs the folders to their local(remote) machine. When someone makes a change, it is synced back to everyone who is using the client, including the local(in office) network share.
Once it's set up, it's transparent and you just work the local files.
There's also ways to do this freely, but I don't know how in depth you want/can go. Also, not sure how easy it is on Windows, as I and our company run Linux exclusively.
The archived data is archived in the sense that it is not usually being changed or actively edited, but it is frequently referenced for a variety of reasons. Any time we do a job for a company that includes previously tested sources we need to reference the archived data. Or if we do a job that involves the same methodology, etc. It comes up frequently enough that access to anything less than 100% of the data and old reports would be unacceptable imo.
I have set up something similar to a dropbox where multiple personal computers were synced up. I set it up because I wanted my music folder (and a few other things) available to me in 3 locations* and I wanted to be able to add music to any of the locations and have it all synced up similar to dropbox without having to manually transport/add files to each computer. These were all windows based computers, and initially I had success, but it seems that without constant tweaking of the settings that the functionality eventually breaks down and things stop syncing correctly. It ended up being more effort, and less reliable, than manually transporting the files with a usb drive so ultimately I gave up. It still works most of the time, but I have to check on it to verify some of the important stuff is in fact synced across the other computers.
*This also functioned as my back up plan. I didn't need a separate drive to back up any of my personal files if there are 2 other computers with the same content. If one computer gets fried I should have 2 complete back ups elsewhere.
Really the main functions I would like to solve with the VPN is being able to have my coworkers directly access the shared drive remotely so they could put the data they have on it rather than emailing me all of it and having me put it in the appropriate folder (or more likely they forget to email it until I go to work on the report and there is no data, so I call them in the field and it's a clusterfuck and I have to wait until they have internet access and they email it to me). I also would like to eliminate the scenario where they need to work on a report, but are not in the office, so I have to email them all the data, along with any other template spread sheets and word documents they may need, and then when they are done they have to email it all back to me, and I have to delete the old data and replace it with the revised and manipulated data. It would be much less of a headache if they could just remotely access the drive directly so when I go to work on it I know I have the most up to date version of everything. It takes time from both parties to do this, and it interrupts my workflow. I would say one of the these scenarios happens on a weekly basis, sometimes though it's much more frequent. This week was particularly bad with 2 other people trying to work on the same report. We ended up with multiple copies of some documents, some documents didn't make it back into the folder at all, and I had to hunt through multiple emails to sort it out, all while not doing the original project I was supposed to be working on. This week is really what prompted me to set this up because it would have made my week much smoother and less stressful.