Am I not right in thinking the Carina e is pretty much the same as a 1st gen Avensis, same basic body and running gear?.

If so, while I wouldn't be against getting a Carina e, I'm not sure why you'd choose one over the Avensis unless a particularly nice example has cropped up locally. As reliable as the Carina e is, being the younger car ('97-'03), presumably there will be more examples of the Avensis out there to choose from?.

Didn`t the Avensis have gearbox problems unlike the Carina e, friend of mine had Carina e for over 10 years without a problem, and then bought an Avensis to replace it but had 2 new gearboxes fitted in 5 years due to a bearing problem, some were notchy gear changers and some noisy, correct me if wrong?

Had a P-reg one on hire many years ago. I think it was virtually the last of the Carinas, the 1.8 E model. It was one of the very few hire cars that could match my Cavalier for fuel economy. Something tells me that they were galvanised. If that's true then maybe worth a punt but it will be a very old car so some spares may be hard to get.