- ELI5 what "free for 50 sheets" mean : This means that you can upload 50 PDFs that contain your plans (Blue Prints). So if you are undergoing house renovations and your Architect drew up plans that are 25 pages, then half of your quota would be used.
- Is there any benefit in using it for small, private projects : That depends. If you're outsourcing your work and have a contractor, then yes. The plans are initially updated on the service and any revisions that occur throughout the project would be instantly synced.
PlanGrid, from my limited exposure, is a markup tool for the initial plans. Their goal is to keep everyone in the "know" with a project that constantly changing. If you and a buddy are working on a deck, might not be useful. If you are contracting/sub-contracting work, it will be very useful.
My 2 cents.
If nothing else, if you have a construction project that has paper plans, PlanGrid is the best way to make them digital, shareable, usable by multiple people.
Is the point to be a full document control type solution (e.g. - in the same vein as Aconex) or is it a collaboration tool focused on construction? It appears to be the latter?
I guess I could just ask one of the guys I know from DPR...