You're right... I did not explain this very well... you said:

"You seem to be describing your Purchase, not a Sale, here: "We occasionally buy books or order tshirts to sell but usually pay when purchased" That is your Write Check or Enter Credit Card Charge/"

OK... trying again...

If i buy some books online or at a store to sell and I pay immediately, that's a purchase for me, so to properly record this, do i use...

- Vendor > Enter Bill > Save and then Vendor > Pay Bill > Pay Selected Bill or

- Nonprofit > Enter Bill > etc... same options are available (does it matter?)

or you're saying just skip all that and when i purchase something and pay immediately, I go directly to Write Check or Enter Credit Card Charge ? If so, when do you use Vendor/Nonprofit path?

and then when i sell the book to a customer, do i use...

- Nonprofit > Receive Payment (Customer Payment window) ?

(I'm sorry... I will ask just one question at a time to try to be less confusing...)