4WD RAV4's are not able to be flat towed because there is no transfer case to put in neutral. The system is an all wheel drive system which uses a viscous coupling to give the 4WD. That coupling will be damaged if towed.
I am sorry for the discrepancy in the information that you have received. I am not an RVer and don't know all the ins and outs of flat towing. I did read the article you sent me and in the article it stated that only the vehicles owners manual can accurately tell you if the vehicle can be safely towed. I looked up a 2003 RAV4 owners manual. It didn't say anything about recreational towing. It did, however, have a warning about emergency towing - it stated that if a commercial towing service wasn't available and you NEEDED to tow the vehicle, you could flat tow it but only for SHORT distances and at LOW speeds. I'm going to assume that you'll be towing for longer distances and need to be at least close to highway speeds. Maybe the site that gave you the information has tried towing a RAV4 with success. I was simply trying to be extra cautious as to not give you poor advice and subsequently cause damage to your vehicle. I certainly don't want to deter you from buying a RAV4 - more Toyotas on the road is better for me! I hope this information is of more use to you. Good luck with your vehicle search.