If you purchase an Aibo be very careful while purchasing it. From experience I can tell you that unfortunately people who sell Aibos online seem to think it's ok to overcharge you for them while neglecting to describe them accurately.
Also although you may be aware the item you purchased for thousands of dollars is very valuable to you don't expect that to matter to the seller or postal services as nobody cares and it is very easy to get caught in the trap of overpaying for an Aibo and being sold a product that does not hold the same value as what you paid for it due to defects and signs of wear etc that make it impossible to recoup what you originally paid when trying to transparently sell it again later.
Be aware that an Aibo only devalues with use, so unless your planning on keeping it and using it for the long term they do not make good investments because they are not rare enough to ever increase significantly in value. The "limited edition" models and colors tend to get over hyped on the forums and are really not as valuable in the real world as the perception you get from reading forums has you believe.
In fact looking at the first generation, the 110, of which only five thousand units were made, and almost 15 years later you can purchase one that is "as new" for under five hundred dollars, that's significantly less than their official retail price of US$2500.00(Yen 250,000) and is very low when you consider their rarity.
If deciding to go with an Aibo I would avoid the following model
1)ERS-7 Mind 1 with a affected serial number. You can find the numbers here:
http://aiboaddicts.yuku.com/topic/40#.UdmGb9hNfw4%22If you purchase a Mind 1 with a number that is within the recall range but the seller says it went to have a Sony checkup make sure the seller is able to provide you with proof of the this.
Aibo gives you an experience of owning something that is different to owning a real animal and is good if you want a low maintenance companion.
I have never owned a Pleo, but from what I have read and seen of them they appear to be more like owning a real animal in that they need feeding and constant care etc and would appeal to you if that was what you were looking for in a robotic companion.
Also try options other than ebay when sourcing Aibos, their are a lot of cheaper alternatives out their such as the Japanese auction sites as people on ebay seem to over price Aibo for some reason.
Here are some things to expect when purchasing an older generation Aibo:
If purchasing a ERS-110, ERS-111, ERS-210 or ERS-220 expect that they will need to have a DHS repair fix which could significantly increase the cost of your Aibo once shipping and the repair costs are factored in.
Also expect that the battey will need to be re-celled, and it is now possible to have batteries for all the models replenished.
Once the DHS is fixed and battery re-celled you should have no further problems with these issues, so although these things may increase the cost of your Aibo, once fixed they will never create problems in the future. Although the battery capacity will naturally diminish overtime and this can't be helped.
Also expect that due to the age of Aibo that if you purchase any model that it most probably will have ongoing costs associated with it's upkeep.
