IF the goods are still on hand then do a Return of Goods, update, change the price on the purchase order and then do a Receipt of Goods with Invoice.  Otherwise you will need to post the invoice, not the amount of the variance and the GL account it went to. Adjust out the items left on hand and adjust in with correct cost. Note the difference and make a GJ entry taking money out of the inventory adjustment account and putting it into the purchase order variance account.  Note how many items you may have sold and post to COGS account the amount needed to zero out the purchases variance account. That's how I would do it.

Returns won't work properly for some valuation methods (FIFO...) because you don't get to choose the cost tier.

Returns won't work properly for some valuation methods (FIFO...) because you don't get to choose the cost tier.

Dat True, needs to be Serial or Lot