Vetassess- everything to be certified true copies??

lukey

Hello,
After researching I found out that documents need to be certified true copies- Is this only for mail application? Because I'm applying online, so for diploma and certificates, I have the original which I can easily scan to high def. But how about payslips which are only emails from company (they do not issue hard copy to save costs). I had planned to only photocopy those emails. Do I need to have them certified at the embassy too? Pls advice because 10 yrs of payslips to be certified will be Super expensive!
Thank you!!