Price List
I use First Class Mail: postage for 1 towel is 2.50; 2-3 towels is $3.00; 4-5 towels is $3.75; and 6-7 towels is $5.00.  These fit in a manila envelope, though 6-7 often weigh enough for priority mail..

Postage for a priority box is: 8-10 towels is $7.00; 11-13 is $7.75; 14-16 is $8.50; 17-20 is $9.25; 21-23 is $10.00; 24-26 is $10.75 and 27-30 towels is $11.50.

One double towel naturally counts as 2 towels in regards to postage costs.  I usually go to the post office to mail out on the weekend.
Single towels at the cost of $3.00 each
Double towels at the cost of $4.50 each
1 = 3.00
2 = 6.00
3 = 9.00
4 = 12.00
5 = 15.00
6 = 18.00
7 = 21.00
8 = 24.00
9 = 27.00
10 =30.00
11 = 33.00
12 = 36.00
13 = 39.00
14 = 42.00
15 = 45.00
16 = 48.00
17 = 51.00
18 = 54.00
19 = 57.00
20 = 60.00
21 = 63.00
22 = 66.00
23 = 69.00
24 = 72.00
25 = 75.00
26 = 78.00
27 = 81.00
28 = 84.00
29 = 87.00
30 = 90.00
1 = 4.50
2 = 9.00
3 = 13.50
4 = 18.00
5 = 22.50
6 = 27.00
7 = 31.50
8 = 36.00
9 = 40.50
10 = 45.00
11 = 49.50
12 = 54.00
13 = 58.50
14 = 63.00
15 = 67.50
16 = 72.00
17 = 76.50
18 = 81.00
19 = 85.50
20 = 90.00
21 = 94.50
22 = 99.00
23 = 103.50
24 = 108.00
25 = 112.50
26 = 117.00
27 = 121.50
28 = 126.00
29 = 130.50
30 = 135.00
While I have not yet mailed out 30 double towels, I have crocheted 108 singles for a convention. Someone contacted me almost a year in advance where they sent me 54 full towels of one design, a pair of cowboy boots with the state flower in them.  She bought them in her state and mailed me the 9 pillows of 6 towels each.  I cut them and made 108 singles and mailed them back.  As I've often said, the crocheted towels make a unique gift and this was a very special gift for all of the conventioneers.  As you can tell, I'm a bit proud of this one.  I loved the towel and it was joy to work with that large an order.

Other than the convention, I have mailed out an excess of 30 single towels for people who have bought towels for their office as Christmas presents and Thank yous (often bosses for their employees).  A $3 gift with a bit more for postage is an inexpensive gift and while some pick just a few towels for people, others have fun choosing more selective towels for individuals.
The above price list is for most of my towels.  I did not make a list for $pecialty towel$ or Towel sets.