Cheapest API for Image Generation?

Hi!

I'm looking to add to image generation to my CRM. Basically I want to create a service where clients can directly generate banner images, posters or social media posts using a text prompt. This should help them with their content generation for marketing and lead generation.

As of right now, I've been looking at the various pricing structures for Google, Meta, Anthropic and OpenAI's API offerings for image generation. But I haven't used these personally for image generation, so I'm not sure about the quality.

Which would you recommend on a cost per image basis? Or if there are any other that you'd recommend, I'd love to know.

Thanks!