Invoice/Receipt

I dont post here very much, but thought maybe you guys could help clear up someting for me. I am getting more into tracking sales and everything this year. I need a little clarification about invoices/receipts. My clients pay me in full at the time of the shoot. Would an invoice be pointless to give them? An invoice basically shows what is owed, but if they are paying at the time that I am making the invoice would it make more sense to just make a receipt instead? Or would making an invoice and marking it paid be enough to avoid making a receipt? Sorry if this is confusing. Thanks for any advice you guys have!!

You don't say what applications you are using to generate your invoice and/or receipt. What are you really wanting to track, what is your objective in this.

Invoice vs. receipt, I don't think it matters which way you do it as long as you are consistent and it meshes with your software. If you have a high gross then this is probably something that you should be asking your accountant.

I think that the term "license" would be more appropriate. My first document is an Estimate containing the projects details, licensing and payment schedule. I require a retainer of 50% and the balance due on the day of the shoot or within 30 days depending on the Client. My final document is a license and it will have the check numbers on it.