We have a big dog and 2 cats in a 310RL so decided on Temu's Sherpa plush thick no slip sofa covers. For the back and seats I have 2 separate pieces (same size) and I also got 2 arm rest covers. The separate pieces allowed for a variety of color combinations versus just one color. The 2-seater sofa cover is a perfect fit with just a little part of the back of sofa peaking out on each side. Since we have cats I liked the cat ones.
Sorry I didn't make mine level and RV new so I still haven't removed original plastic on seats
Matching pillow covers are also available.

If you don't like this style, there are MANY very sophisticated covers in many colors and patterns and very inexpensive.