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I did that when I was in Plano, Texas. I went to a thrift store and bought a suitcase. When it came time to check my luggage of course I checked all my clothing and carried on the fabric. The suitcase was full of batiks from www.fabricfanatics. I was overwhelmed when I walked in the door, bought some fabrics and went back the next day after a good nights sleep I was ready to shop.
I live way too close to M & L. Even though I don't need any more fabric, I always find something to buy. Way too dangerous!
When we travel, we always leave room for bringing back extras. But, if we've been extra spendy at his family's place, we have a spare suitcase we trade back & forth with his brother. When he comes here to visit, he and his wife to all their clothes shopping, because the prices are so much cheaper than in Denmark where they live. When we go there, we load up on foods and candy we can't get here, fabric and thread (I can get a 2000 meter spool of GOOD thread for $4 there), and and anything we got as gifts to us or that we bought for others here. We check 1 less bags going over than we have people going, then have 1 each coming home. It works for us!
Since you didn't expect to do this, I'd say either a carry on from a thrift store or shipping it home is your best bet. Flat rate boxes come in many sizes, with the largest being 12x12x5-1/2. Anything you can stuff in there, ships at that flat rate. Since it's fabric and has to be washed anyway, line the box with a plastic bag & cram away!
Package the fabrics and mail them home. When you get home you will have it waiting for you. Almost like reliving your vacation all over again. Enjoy! If mailing I would recommend both insurance and delivery confirmation.
I visit my sister in Oregon every July, and every year I do the same thing. I always end up sending at least one box home, and my luggage is bulging!! LOL
I always send myself a box of fabric when I travel. It's easier than wrestling a heavy suit case on to an airplane. I use one of the boxes from the post office and just bring some packing tape with me. So easy.
I have also been known to ask a store that ships to send my fabric, and have even asked them to include fabric I bought elsewhere. They have all been very accommodating.
I'd rather be at the lake
Do one thing every day that scares you... Eleanor Roosevelt
I love the priority boxes at the post office -- when we traveled in the US I would pack a box and mail it home. In Alaska, the shops sent the boxes for me (they were WONDERFUL!!!!). In Hawaii I could not have made it home without sending the boxes priority. In addition, it was fun opening the boxes when we got home.
When life gives you lemons, make lemonade.
I'd say mail your fabric home the day before you leave.