Rental car advice
 

We will be driving through the Mosel Valley in Germany and will then be dropping the car off to catch a train to Belgium, Netherlands, etc.
I currently have it planned to drop the car off in Luxembourg and catch the train from there. I know there is a hefty drop off fee. I'm okay with that, but I want the easiest place to drop off the car and catch the train. We are renting from SixT and it looks like the closest place to drop the car is the Luxembourg airport. I'm thinking we could then Uber/taxi to the train station? Is that reasonable?

The other option would be to drop the car off in Trier, Germany. I would avoid the drop off fee. We can then catch the train in Trier to Luxembourg. I'm not sure where the rental car drop off is from the train station in Trier.

What do you recommend??

Sixt (or google) can't tell you where the dropoff point is in Trier?

Sixt has an office in Trier. Ottostrasse 6. 24 hour return.

Luxembourg would be slightly better timewise for trains to Belgium and Netherlands. But, don't miss Trier - so many neat historic sights - some of best Roman relics north of Alps - so-so - which means pleasant - typical larger German city - great pedestrian shopping area.