It’s all about the message you send, not about the money you spend.
A pack of markers can say more than you think.
My husband worked in a clinical lab where he tested patient samples. It was repetitive, mostly automated and highly regulated. There was no room for him to be creative with a test, nor should there have been. However, he did get a new, disposable, lab coat every week, on which he had to write his name. And every week, he would find a unique way to write his name - a new abbreviation, a different color, an original format. Through this, he was able to bring a small part of his creative self to his highly repetitive, machine-like work. Each week, with a simple marker, he declared his humanness and said to the world - "I am not a cog in a machine. I am a unique, creative being."
Where can you provide space for, not force, your employees to feel more like unique people than cogs in a machine? Does one of your walls need a mural? Do you need someone to brainstorm new ideas to add beauty to your business? When you provide space for them to bring their creative selves to work, it will send the message that you value them as unique, creative humans, not as worker bees that can easily be replaced. You’re saying to your employees - “I see that you’re a unique and creative person. You’re not a machine that I’m using to make money. You're a human.” On top of that, imagine the inherent ownership and care for your business that employees might feel if they created something specifically for your business. If people feel that their uniqueness is valued at their place of work, it may be fair to assume that they inherently won’t be as likely to leave.
It really can be as simple as a box of markers. However, do it genuinely, because it's not about the markers, it's about letting your employees know that you value them as the unique people they are.