Since you are sending it to your daughter and, presumably, tracking is not an issue you might as well jut bring it into the post office and pay for it over the counter. You should be able to send it as either an oversized envelope or a "flat" both of which will be less than he $2.90. Neither of those services are available on line.
As for the items you sell on eBay you can do the same thing BUT you will not have either tracking nor proof of delivery. So if a buyer says they never got it you will automatically lose the case.
So on inexpensive items it becomes a trade off. Will you save enough on postage to cover the refunds you will be forced to give to the buyer who says they never got it? If these are common inexpensive items the probability of a FALSE not received claim is most likely very minimal. But as the value of the item increases so does the likelihood of FALSE claims. Only you can balance the risk/reward on that. We all have an opinion but it fairness it us YOUR wallet on the line, not ours.
"Laissez-faire capitalism (AKA The Great Material Continuum) is the only social system based on the recognition of individual rights and, therefore, the only system that bans force from social relationships." ~ Ayn Rand
