I've had several questions about how planning for the Appalachian Trail works. I'll speak from my perspective on this topic as per usual, but in a nutshell.
It's hard. Planning is hard.
We started out just planning for all the equipment and supplies that would be needed. I had a list and a notepad. Every time a new item popped into our minds; I'd write it down. Not all items were actually bought but we kept track of the list. Slowly, we started purchasing the items when they went on sale, or we had a coupon for them. I can confidently say that around 90% of the items we purchased were on a discount of some sort. We were buying two of everything, so we needed the sale price.
Then, it comes to actually planning for the months long trip. Jeff had to talk to his boss and get permission to do this in the first place. The start date was kind of tentative at first. It depended on the weather. Jeff decided he didn't want to be in the midst of the "bubble". The bubble is a dense cluster of people that start at Springer Mountain heading north at around the same time. Getting ahead of that massive group of people helps you with space in the shelters and honestly, sickness too. The date of February 11th was set. Jeff's 48th birthday is February 10th, so it felt like a good date to start the great adventure.
As far as when I go to visit them, I learned after the first visit that I cannot book a place to stay until MAYBE 3-4 days beforehand. Trying to find an Airbnb or VRBO in such short notice is very hard. You end up with very limited options. You'll have a house that's too big or too small and never everything you'd really want. I book houses usually instead of hotels for a couple of reasons. First of all, their gear takes up a lot of space and it's stinky! They open up and lay out everything to let it air out and dry completely. Secondly, you'll likely have to go out to eat for every meal. You might find a hotel with a free breakfast but that's it. Jeff and Gavin really have been wanting home cooked meals even though they will still take a pizza in a minute. Lastly, a lot of the time you can get a house for around the same price as a hotel room. It just kind of depends on the location and your standards. Sometimes you get a discount for booking so last minute with a house.
If I go visit them on one weekend and plan on going the next, I don't even consider looking for places to stay until I get back home from the previous weekend.
When I do come and visit I bring all the food they will need to resupply for the most part. It's a couple dollars cheaper ordering their meals from Amazon than picking them up at an outdoor supply store or Walmart. I feel like it saves some money but pretty soon they will have to do all their resupply by themselves. If you're interested in seeing what all we've bought check out my Amazon storefront. I've tried to add everything and I've tried to keep it updated.
Let me know what questions you may have!