Saas Pricing - When to charge for Seat based pricing

I just built a Saas with a couple of users (<10). Currently not charging them since i needed to do some PM fit validation for the next month.
Product targets Individuals and Small Businesses with simple usecases and considered a standard monthly price for all users.

I anticipate a shift in strategy to target Enterprise B2B companies in future. I thought of adding Seat based pricing per user. However i feel this might spook the same individuals/small businesses if i launch this as the initial pricing model. I currently also don't see ( haven't validated yet too) the product's value in a company scaling / being more impactful by having more users in the organization set up.

How would one go about pricing for such kind of Saas ?