Custom CRM Development Cost for a Small Business

I’m helping a small service business move away from spreadsheets and build a custom CRM, and I’m trying to get a realistic idea of what development should cost.

The CRM would be web-based with multiple user roles and different permission levels. It would need customer profiles, order management, inventory tracking, and the ability for an admin to assign orders or tasks to specific team members. We’d also need a payments section for tracking basic financial stats, plus invoice generation and printing.

Nothing extremely complex, but it would need to be reliable and leave room for additional features as the business grows.

For developers or business owners who have built something similar, what would you consider a reasonable minimum or average custom CRM development cost in USD?