Renault Trafic gearbox issues.

Hi. I have just put a £200 deposit on an ex AA renault trafic 10 reg with 51000 miles and am supposed to complete next Tuesday. When I showed a photo to my car mechanic he said "don't buy one of those. They are rubbish" so I had a more in depth look at any issues. Now I am panicking that I'm spending £8000 on something with a gearbox that might disintegrate at any moment, taking my money with it. Is this likely to happen. Could I have the bearings replaced before this happens to pre empt a disaster?



As a small time gardener I'm already scraping the barrel and don't have the money to cover any such disasters. I'd be really grateful for any advice.



Cheers