exp has nothing to do with it, its your stats. if it says recommended 3500 speed, you should have 3500 speed to be able to do it most of the time. minimum nerve required is a must. look at the links in my signature. they are a bit better presented

have a look around the prison. the first one you can do is raid the janitors closet, its in the main hall. for requirements, click the new jersey link just below this message

But I'm not even close in speed, I'm still around 1200.

Wont I be able to raid the arcade until I get around lvl 8-9?

Maybe it's just because I don't understand but I would be grateful for any help.

putnam crimes have high requirements, to be honest you shouldnt be criming anyway better off sticking to training, if you need money do some runs, its better that way, trust me level is nothing in this game