Making sure we have an extra stock of monitors, computer parts and even printer toners is important because if we don't keep track of inventory someone will be without support or the ability to work for a while, which effects the business. The same goes for land - if you don't keep track of fuel or oil stores, bags of feed or food you could be in a world of hurt and the only person you have to blame is yourself.
A strong cataloging skill-set helps keep you prepared for weeks, months or even years ahead. And the more organized you are the more efficient you can be. If you buy lots of things in bulk you will probably save yourself fuel and time because you're making less "emergency" trips to the town general store or Home Depot because you didn't realize you had run out of X, Y or Z. Or less individual orders online, which save on shipping costs depending on the vendor.
It may seem obvious, but most people I know who own bits of land or have a small business may only know what they have in their head or not at all... not smart. It will come and eventually bite you and you'll hate yourself when it does.
Learn to be one with spreadsheets because they are your best friend - believe me.
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For example:
One section can be for supplies just for vehicles such as: fuel, oil, extra tires, etc.
Another section can be for specific amounts of building materials such as: nails, wood screws, 2x4 boards, etc.
Lastly you can dedicate a sheet or tab (in Excel Spreadsheet) to food and water stores like: bags of rice, spices, etc.
The better equipped you are doesn't always make you the most efficient. The more knowledgeable about what you have will make you more efficient.