XRAY - Model racing cars

I've wanted a series 2 rx8 for a while now, and I was wondering if it is better to look for one that is in good condition or to simply buy one with a dead or almost dead engine and than rebuild it. I've been finding S2 Rx8s from 8k to 12k. I've also calculated that the total rebuild cost will be between 7k and 9k. I will most likely pull the motor myself and take the engine to a specialist. So I was wondering if it will be worth the hassle of fixing one up. If I do get an 8 I would like to drive it for at least 5 years but who knows what will happen. I would be very thankful if some of you where willing share some advice.