Hi!!
Both campuses are fairly nice. The accomodation on College Lane looks far more modern as it was updated more recently than De Hav (with the exception of Telford Court, which hasn't been remodelled to the same extent).
The interiors it really depends on the type of room you apply for. There's a Standard Room, Enhanced, Townhouse, Twin, Studio and Single (Telford).
I am currently staying in a standard room, and it's very nice. Has a large desk and decent amount of storage space (under the bed, in your wardrobe and in drawers). It also has it's own personal bathroom. You share a kitchen with your flatmates.
Enhanced is pretty much exactly the same, but a queen size bed instead of a single and more storage space for a much larger price. I applied for enhanced and was disappointed when I got standard, but honestly standard feels pretty much the same.
Townhouse I believe is similar to a standard room, but you don't get your own personal bathroom, you have to share it with one other person. I think there is more floor space in a townhouse.
Twin rooms are pretty big, you share a room with one other person. You both get your own desk and wardrobe, and you share a bathroom within your room.
Studios are similar to Enhanced/Standard, but you get some kitchen equipment too so you can cook your meals in here. You get a table and your own bathroom.
Telford is similar to a standard room but it's laid out differently, and you don't get your own bathroom. From my memory, you share a bathroom with one other person.
You can find photos uploaded onto the university's website, and if you look on Youtube and around the internet you can find photos that people have uploaded too.
( university's website
https://www.herts.ac.uk/life/student-accommodation )
Majority of people tend to prefer College Lane's rooms over De Hav, but De Hav's rooms aren't bad.