The number is really just a personal preference; more importantly are proportions and creating a well balanced vignette (which includes how the sideboard is accessorized). Look at inspiration pictures to identify the layout you prefer and chose art that resonates with you and the room.

The next step is size and proper placement.

I love framed botanical or animal prints in a traditional home. See examples:

Naples Florida Vacation Home - great room bird prints · More Info

Botanical Prints · More Info

Dressing a house with art · More Info

Chispa is absolutely correct. I don't have anything on my walls that isn't meaningful in some way (like the quilt my mom made), or that I absolutely love. Finding something you love takes time.

A framed poster is an inexpensive way to add interest, while you look for just the right thing.

I have never chosen art for a client and will not do so now. Art is chosen because you love it . IMO one well loved piece is the best over that buffet . If you do not want to go the original art route at least go look in galleries to see what you like. I use Art.com to suggest to clinets not into the price of originals .Yes we do need to see the whole space lease post that her ein a comment. The other place to look at art is an art college if you have one near you. We find searching for art a really fun way to spend a Satruday afternoon

We don't know your age. If you are relatively young, you have time to find art.

But, if you older like me, sometimes you just want things finished.

I found a few art pieces on Wayfair for my Florida home. Not expensive.

I also commissioned a local water colorist to paint a few pictures.

Peruse Wayfair, lots of ways to filter down what you like. It can be a space saver if you later stumble on something better.

I would get one picture. Google the formula for how wide and tall it should be after measuring the space.

Four small framed paintings, or one large painting, might work really well with your console. Try looking at some artwork online, or locally, to see what you might like to buy for over the console.

Modern Organic · More Info

Curated Colonial · More Info