Project Change Orders and Additions

Project Change Orders and Additions

We are in the process of migrating from QuickBooks Online to Zoho Books. We have Zoho One and like the ability to sync all of our data across everything. And I like that projects work in a way that's less dumb than QuickBooks. I'm trying to figure out something and hoped that you all could help.

We are basically an IT general contractor. Our projects are mostly fixed cost, so the fixed cost option in Zoho Books/Projects works great. The question is about invoicing above and beyond. Sometime the client changes the scope of work, and we charge for those as a change order. In Projects, it's basically an invoiced Issue/Bug.

Is there a simple way to add an item or charge to a project? Can a Sales Order, Expense, or Bill allow us to invoice for additional amounts? Or do we need to adjust the Fixed Cost (which would suck cause we need to do that in Projects)?

Thanks!