Thanks. I had already seen those ads too. I really don't understand how they sell them so expensive. I also do not understand why there are so few available (it is assumed that many units of this phone were sold when it was released).

I do not want to spend a lot of money and, also, the prices I see are too high for an old phone (also, it was not a high-priced phone 10 years ago, it seems that now they are trying to sell it high because there are few units for sale) .

Right now the only one that I see as a good price is the Red one, from Sprint (on eBay). Interestingly, it seems that this model (red), despite being from Sprint, only has 64 MB (instead of 128 MB). The big disadvantage is that this ad is from the USA and, in addition to the € 20 shipping cost, I am sure that I have to pay € 30 more for the import (very common to have to pay a high price from Customs in Spain for a product from the USA or from outside the EU).

The listing also does not include the box, charger, or back cover. Although for that price I would buy it if the ad was outside the EU (€ 20 is a good price for an old phone and shipping would be around € 10 or € 15).

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Upgrade:

Well, I have seen that it is very difficult to get a Palm Centro for a not very high price. I love this mobile aesthetically, but what really interests me is Palm OS 5.4.9. So I have seen again the phones that I had discarded (and that have Palm OS 5.4.9):

(There are also some PDAs (Palm TX and Palm Z22, as well as other non-Palm PDAs) with this version of OS, but I'm only interested in phones.)

Palm Treo 680: GSM. PXA270 312 MHz. 64 MB available for the user. SD.

Palm Treo 700p: CDMA. PXA272 312 MHz. The antenna sticks out of the body (negative point for me). 64 MB available to the user. SD.

Palm Treo 755p: CDMA. PXA272 312 MHz. 64 MB available to the user. MiniSD.

They are very similar, the decision would be between the 680 (GSM) and the 755p (better CPU and miniSD). As they are almost the same, here I would choose the 680, since it has GSM and will be easier to get in Europe.