how to tell serious damage?

[eastcoastS14]

since i totaled my last 240 ive been looking to find another, i found one for sale on here but the seller said that the car has a clean rebuilt title...price is good the only thing that i am worried about is damage that would not be apparent just from the outside supposedly the car was in a collinsion that damaged the front driver side...you cannot tell at all from looking at the exterior. My question is what should I look for for to tell serious damage? the car is in another state so i cant really get there just to look at it but would make the trip to buy...at this point i am thinking that i will have the seller take more pics...so what should i request pics of to make sure there is no serious damage? I am going to carfax the car as well just wanted to know what to look out for