Step 1: Break down the pallets
I got about 80 pallets, five at a time, from my work.
I got a chance to know the facilities people and they were very happy to let me take them. It saved them a trip to the dumpster and saved them from having to pay to have the dumpster emptied.
That's right. Almost all of these pallets go directly to a landfill. The rest are picked up by pallet salvage guys (they get $1 or so a pallet) and people like me. Many people burn pallets for heat.
I got a great deal of exercise carting the pallets out to my Jeep. I could fit about eight at a time, but I rarely found more than five good ones on any given trip.
A few words about pallets:
There are all sorts of them. Some are oak, some are pine or spruce. Some of them are even mahogany or cherry or cedar.
Stay away from the hardwood pallets. They"re almost impossible to deal with in large numbers. They are just too darn tough. Unless you're doing something small or you want them for fire wood (They are awesome for that), stick with the pine or other softwood pallets.
About one in ten of the ones I found were high enough quality. Most were garbage. I tried to find ones that were brand-new, roughly 48" x 34", and were constructed of (3) notched 2'x4's connected by 3/4" inch nominal boards (commonly called "one by" lumber.) All of them were heat treated (marked "HT") and held together by nearly indestructible spiral nails.
Many people assume that pallets are pressure-treated. In my experience, very few, if any, have had any sort of treatment besides kiln-drying. I'm told that years ago they were also treated with pesticides, but this is no longer the case.