IF IT'S NOT Q.P.A.C.E.
IT'S NOT IN MY KIT
ABOVE: I love to help people (from beginners to "old" photographers alike) discover that filmmaking can be easy, and my 1 tip "Always shoot with (at least) two cameras" is the most important thing that makes video production easier...
QUALITY
THE GEAR MUST BE CAPABLE OF PRODUCING PRO CONTENT
I never want the term "low-budget" to mean the quality is going to be bad. So, getting good quality is a non-negotiable aspect of my KIT PLANS. If the gear can't produce professional quality, there isn't a reason to brag about producing on a low budget!
PORTABLE
THE KIT SHOULD BE COMPACT (TO TRAVEL OR MOVE QUICKLY)
What do I consider portable? To me, it means I can travel with the KIT by airplane. This means it will fit in 3 pieces of luggage: 1 LARGE piece (checked luggage) 1 MEDIUM piece (overhead carry-on) and 1 SMALL backpack (stored under seat on the airplane).
AFFORDABLE
NOTHING ELSE MATTERS, IF YOU CAN'T BUY THE GEAR
If you can't get the gear, you can't do much else. So, it's important to be able to afford the KIT PLANS. With all of the good budget filmmaking LIGHTS, CAMERAS and AUDIO gear out there nowadays, I do think it's possible (it just requires good SETTINGS).
COMMON
GEAR NEEDS TO BE EASY TO SOURCE (NEW OR USED)
If you ever need to replace items that are lost or stolen, you not only need to have enough money to buy the KIT but the products also need to be commonly available (easy to find in your local new or used market).
EASY-TO-USE
IT MUST BE EASY TO USE, EVEN UNDER STRESS!
There are several reasons I think this is important. The first is simply that it makes it much more fun. The second, is that if you make your methods (HOW-TOs) simple enough to do under stressful conditions, they will be super easy to do when you're NOT under stress. Additionally, simple processes are much easier to teach your team.