Hello everyone, I've been watching the videos and courses, but i dont think I've sumbled upon this "problem".

I have this Sale. It's ready and the invoce has been made. Is there a way I can Forcefully avoid even myself of changing it? I can imagine that making a smart button "Close Sale" could do it. But I am wondering If I am missing something more obvious. 

This question was raised to me and I honestly dont know the answer to that. 

A second question that was raised was: "I have sales that must be kept open for 1-2-3 days/weeks because the client buys in bulk and sometimes request more items or removes some and until the truck comes, I have to make changes... but then, why would I make a new one it if i can always keep it open?"

I honestly dont know how to answer to that question more than saying "I understand, closing the sale and making a new one lets you have more traceability when searching for products or dates" but then again.. seemed like more a "opinion or liking" more like a "you need to do A for B to happen"