While it has been discussed many times here in different threads, a few things that should be mentioned that were brought up in various posts in this thread.
1. DHL may be cheaper, but they do not allow reptiles. If they discover a reptile shipment, they will stop it in transit and it will be the shippers responsibility to pick up the package wherever it stopped. If you are in NJ and your customer is in CA., it gets stopped in Kansas, you need to pick it up in Kansas, or it will be destroyed.
2. Fed-Ex requires an application process and you need to send them a shipping box to test. Once you get approved, there is still the clause in the contract that says you can only ship to a "business address". UPS accounts can be created in minutes from their website. Print out this poicy
http://www.ups.com/content/us/en/resources/prepare/guidelines/animals.html and bring it with you in case the counter person doesn't know what he/she is talking about.
3. You no longer need a special waiver to ship harmless lizards via UPS, snakes are still against there rules. Just set up an on-line account. NEVER use a "UPS store" they are independantly owned and operated. Besides them charging you more, the package also sits in their building until UPS comes to pick it up. I use the actual UPS shipping hub and bring my boxes just before they close at 7:30 PM. This reduces the amount of time they are in the box.
4. Neither Fed-ex nor UPS will honor any claim for lost or damaged reptile shipment. You waive that right when you ship with them. DHL doesn't allow reptiles so filing a claim with them is a waste of time and is liable to get your DHL acount cancelled.
5. USPS allows harmless lizards to be shipped, again no snakes, but they also will NOT guarantee next day delivery, even on their overnight service.
Overall, I have shipped a lot of geckos, at first UPS had me get a special waiver to ship geckos before they changed their policy. UPS may be a bit more expensive, but they have been worth it to me as they are about 99% on time so far and have never lost or damaged a package for me. I would rather pay extra and know that the geckos are spending less time in transit. Since the UPS dimensional weight rule went into affect, I have changed my shipping charges from a flat fee to "actual shipping", I have found that after explaining the shipping charges to customers, and my reasons for using UPS, that they don't mind paying the extra shipping costs.
Keep in mind that for me it may be a bit different as I don't usually ship a gecko that is listed at less than $200. My "lower priced" geckos either get grouped into a package deal that justifies the shipping costs, or are sold locally at reptile shows and to the local pet store.
Hope this helped!
