Home baked pies can be messy to transport. If you use a 9 inch pie pan, you can separate and stack your pies by using the plastic paper plate holders made for 9 inch plates. Flip them upside-down and clip the tabs to the pie tin. This will also give a little room for meringue, and usually vents to prevent condensation.
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There are quite nice wicker plates that are made to hold paper plates. I have found lots of them at yard sales, and never pay more than 25 cents each for them. I use them for craft projects, but of course, they work well for their original purpose.