Looking at small cars ( group C) for a 1 week rental I am seeing 172.73 EUR plus tax => EUR209 from BCN ( with no CDP )

The drop fee is unsurprisingly high at EUR968 inc taxes

using points will remove the base cost but will not remove one way fees

The only way to reduce the cost would be if there is a valid CDP that you can use that has no one way rental fee. I would be surprised if you found one for that