Ok, so been doing some reading and searching. Here is a gun guide which helps to save money on which to buy.
http://www.altergamer.com/payday-2-general-weapons-guide/
Payday 2
It does get scary. Here is also a "walkthrough" on the game. Use it more of a brief on classes and what needs to happen on the heists.
http://www.gamesradar.com/payday-2-essentials-guide-walkthrough/
http://www.gamesradar.com/payday-2-essentials-guide-walkthrough/

