Well, a platform like freelancer is designed intentionally such that you can't, or at least shouldn't, build contact with clients off the platform. Otherwise you and your clients have no use for freelancer.
When you starting to work on project getting e-mail is just matter of receiving/sending deliverables for the first time. If the client is good usually he/she proposes to move away. As when people find devs/designers etc. which they can trust, usually they stop looking around for new ones. Except you are getting on board with some shady company which makes cheap websites for small businesses
Some people would still prefer to use the platform as protection, with their escrow-like payment service.
There is no protection against fraud on Freelancer. If a buyer issues a charge back on his credit card after the project is paid and delivered, you are screwed. Freelancer declines any responsibility for cases like that.
Unfortunately this is the case. I hear that Skrill is safe in this regard. I have had bad experiences with Paypal as well. Do you have any recommendations on what is better way to get paid?