As @TaxGuyBill said the IRS points taxpayers to. The Taxpayer needs to establish an account and log on to "Get Transcript" once they get there they need to select 2020 Account Transcript and the payments will show there. It is quite a task for many taxpayers to go through. There is no way for the preparer to do this without a POA. 

I did look my estimated payments and the EIP (Stimulus) payments received.