For example, if I start the process of filing, with Deluxe, then upgrade to Premier versus just choosing Premiere right away, is it going to cost more?
No, upgrading does not cost more than selecting the higher edition.
If you paid for the Deluxe edition then found out you needed the Premier edition, you will only have to pay the difference in price between the two editions.
No. The fee will be the same amount. If you start out in Deluxe but upgrade to Premier or Self-Employed then you will pay the fee for the version you upgraded to. If you purchased the CD/download and upgrade as you use it, you will pay the difference between the fees for the version you started out with and the version you upgraded to.
No it should not make a difference. If you already paid for the Lowe version you only need to pay the difference in price.
How to review your fees
Or one thing you can do is buy a lower version of the Desktop program like Deluxe. All the Desktop programs have the same forms. You just get more help and guidance in the higher versions. Then you can switch from Online without starting over. You can download the .tax2022 file from online for free and open it in the Desktop program (any version). And the Desktop program has several other features and benefits over the Online version too.
See the Desktop CD/Download program prices here. You also get 1 free state program download.