PLEASE HELP ME - Used x5 purchase!!!!

[_Geri_]

Hi everybody! First off, I'm new here so glad to kinda meet you! =) Alright, so I really need some advice. I thought it would be best to get it from a large group of people who I yet know. I'm in the market for a used X5. I just found one yesterday and I'm doing this all by myself. It's just me, my 3 children, and my very large choc lab doing this buy and I really don't have anybody to help me. Out of all the cars I have purchased, only two were used and both had very very low miles. Now here's the kicker on this one im 50/50 about. It has 140,000mi with a REBUILT tranny. It's a 2001 X5 4.4 and I did test drive it, and it actually drove nice for an old car with a gajillion miles. Here's my thing. Don't older/higher mileage X5's tranny start to slip? If they've been serviced always on time, should I not worry about the engine? I really need help here before I go back today. Anybody??