So I bought I used 7d. and I put a brand new flash card into it and it wasnt working so I brought it back to best buy. I got a 2nd card and same thing. So I looked inside the came and noticed one of the pins was bent. I bent it back and now the cards read fine. What would this cost if I had to replace the inner part at some point?
I don't know what it would "cost" to have that part serviced.... you'd have to phone Canon. They may be reluctant to provide a repair estimate for a camera that they have not actually evaluated in person, but it's at least worth asking the question.
This is an uncommon issue, but not unheard of. When I insert my CF cards I slide them in until they kiss the pins, then gently seat them. Don't force the card in too quickly.
"This is an uncommon issue, ..."
I generally agree with every word Tim writes but not this time. Those pins can even break off! The issue is very common, at least in the world I run in.
It may be that the folks in my group tend to use more cameras with CF cards but I see this a lot. (Most consumer models don't use CF)
I do agree with Tim's method of inserting the CF card. Also you can use EOS Utility to get the photos off the CF card and not worry about removing/inserting it.