Hi Marie,
I'd suggest getting a set of scales(a kitchen scales will suffice).
You can put any weight (your average egg and packaging weight and get the total to anywhere.
I do things 'just the way I do things', but I would never put eggs in a Flat Rate Priority box if the same size box (Priority Mail) would be less expensive (and I llike the size of the Flat Rate Box --- I turn it inside out if it suits the situation).
((I'm in SC, so everywhere is a looong way from here))
$8.65 vs $5.30 in actual shipping (just a random box that just went out).
The usps gets an extra $3.35 per transaction or I don't charge it to the customer in the first place.
Same size box, just the PO doesn't offer a 'not flat rate' box in the same size.
Seems kind of crazy to me to *give* USPS extra money.
If you weigh the box and 'Flat Rate' is cheaper, that's great.
There will always be situations that are different (especially if you are moving a box 'cross country),
but I've rarely encountered a situation where FlatRate is cheaper than regular Priority Rate, unless it it a BIG box of eggs.
Good luck with shipping eggs
It is really exciting for me that eggs laid here hatch all over.
More than you wanted, Marie, but I hope you found a fragment that helps.
I have a breakdown of the cost per egg (my cost) to ship an egg
safely.
It's one of those things
Lisa