Wallerus Stash and Flip?

Half PPR…

I have Ertz but Waller is a free agent…

Is he worth picking up and stashing? The idea would be to later flip him or even Ertz for a bigger name at RB

Who would I drop?

RB: Carson, D.Montgomery, T.Cohen, M.Sanders, Coleman, J.Jackson
WR: Hopkins, Juju, Crowder, R.Anderson, Kirk
TE: Ertz