[chrisandchris]

> As for what I would do - I'd simply tell them that they are more than welcome to become a customer, and that you certainly will take their needs into consideration when prioritizing your roadmap.

Rephrased: In other words tell them to accept your terms, as your current customers pay in total 500/month and you are not willing to customize your product paid by the hour for a market rate.

My take: Think hard how much your independence is worth and how much you are willing to move in another direction because of money. Big companies might want to create long(er)-term contracts and there might be a lot of money in it for you (which you then can use to improve your SaaS). But it also has its downsides, as you will spend time [in exchange for money] for something you probably did not intend in the first place.