If you are looking for a lightweight curtainsider, then the DAF LF should be the obvious choice. Popular when new, there are always plenty to choose from in these truck pages.
When considering which particular Euro 6 DAF LF to opt for you need to think about the type of work the curtainsider will be put to. For long distance operations a higher power version would be most suitable, whereas for local multi drop distribution, the most popular LF150 City is man enough for the job.
Also important is the weight you will be running the truck at. At 7.5 tonnes GVW, an LF180 is well suited to the task, but go up the weight range (the post-2013 Euro 6 DAF LF curtainsiders can go right up to 18 tonnes GVW) then you will need to look at the higher outputs from the 7-litrer PX-7 engine. These start at 230hp and go right up to a whopping 320hp.
You will find LF Curtainsiders mainly with day cabs, but there are sleeper cab options available, but the bed is only two feet wide in places, so frequent night outs would need the larger CF cab.