It is not always 1.71 most of the ones I have sent out have cost 2 stamps like shown and the ones sent back anywhere from .64 cents to the 1.71. I spent some time visiting my local postmaster and this is what he told me. If it is 6x9 or less with the smaller bubbled wrap so can pass through their little checker they have it can go as mail and cost 2 stamps or less unless over weight. If it is over this then it needs to go as parcel which is the 1.34 to 1.71 price again unless it is over their base weight. Last if it has the metal clasp that some mailers have then it is even more as it has to be hand sorted at each point of transfer because it jams up the auto sorter. SO all take the dam clasps off and use tape if you want additional holding power on the opening. Now this being said if a person offering seed for a SASE or SASBE and they ask for 1.71 in stamps for them then this should be the cost regardless of what it takes when they go mail them. It is still a very generous deal they are offering others on here and it is better to over stamp then fall short and expect those offering these offers to pick up the difference.You should also point out that the correct postage in the USPS mind for a Bubble envelope is $1.71. (Your picture shows 2 forever stamps) I have had 3 arrive stamped "postage due". The Mailman has never asked for the extra postage but as the USPS hemorrhages more and more each day they may start to refuse to deliver at some point.
SO, if you use a regular letter-sized envelope (6 1/2" x 3 5/8"), it weighs less than one ounce and you pad it with 2 sheets of bubble wrap that comes out flat and less than 1/4" wide, it costs you a whopping 44 cents. I do this all the time.
A standard 'bubble envelope' less than 11 1/2" long will cost you $1.71.
LOL My favorite is the SASE you get with only 1 envelope. You are supposed to reuse the same envelope it was sent in (which is fine) except it looks like the envelope has already been used 10 times before for the same thing. It is typically covered 100% in packing tape and has multiple old labels. I consider myself lucky if it actually is an envelope... many times it is just the corner of a larger envelope made to look like an actual envelope.
You should also point out that the correct postage in the USPS mind for a Bubble envelope is $1.71. (Your picture shows 2 forever stamps) I have had 3 arrive stamped "postage due". The Mailman has never asked for the extra postage but as the USPS hemorrhages more and more each day they may start to refuse to deliver at some point.
I personally use a piece of small bubble and fold it over the seeds, tape up and in an envelope, but IMO if the person giving the seeds wants a bubble envelope padded with Hungarian sheep wool and blessed with $4 in Nigerian postage, then I simply have to decide if I want those seeds.