evenin all....

Im in the process of maybe getting rid of my subaru impreza

The car im looking at is this

BMW M3 Evolution Saloon Manual (Genuine 1/400 ,amazing example!) Swap WRX/STi - ScoobyNet

I will be honest with you, i have not a clue about bmw s, so i thought the best thing to do was to come on a dedicated forum and throw some questions out

my car would sell for around 4500..... is this a fair price to pay for the above bmw?
what probs should i look out for? i pretty mechanically minded so i know the basics

cheers for any input