I think the parent plus loan is paid to the school directly, so there really isn’t an amount to lend and have repaid. There might be a refund amount (like the money to be used for room and board if living off campus), but the school will keep any amount it needs to pay the bill.
Right now some of the private lenders have really low rates and are lower than the Plus rates. If you have good credit and can co-sign, that might be a good way to go. However, private loans don’t have the same protections that federal loans do. Right now payments are suspended on federal direct loans (Plus loans too? I don’t know) and interest is suspended too through September (and Trump says he’s going to sign an order to extend that). Federal loans also have a variety of repayment options and forgiveness programs that private loans may not have.
I think there is a way to compare the loans and the pros and cons of each type of loan. Check the Consumer Finance Protection Bureau (CFPB) as I think it’s on there.