Trying to finalize consignment calculator with tiered rates

Hello Everyone,

Thank you for taking a look at the issue I am having. Ive spent hours searching online and trying various formulas but cant seem to find anyone that posted the same question.

I am trying to create a google sheets worksheet for a consignment shop. Reason we are using GSheets vs excel, is because he wants to put a QR code on some mailers that lead back to the Google Sheet form which has the consignment rates as well as, a 'Payout Estimator' that customers can use to estimate what they will get paid for an item.

I managed to create the formula using multiple IF statements and was also able to do it using VLOOKUP (both formulas copied from online), but they still don't work exactly as needed.

Two Issues:
1. The main problem is, the owner wants $1 substracted on one of the tiers $10 to $49.99. I can get the total but not minus $1.
2. The flyer says $3 flat fee for items under $10. I could not figure out how to keep the language the same but have the calculator show the $3 fee. The only way I could do it was to change the $3 to 70% which is effectively the same but might confuse customers and also, 70% just sounds more than $3.

See Below:

Sales Price Payout
Under $10 $3 flat fee
$10 to $49.99 85% minus $1
$50 to $99.99 86%
$100 to $499.99 87%
$500 to $999.99 88%
$1000 to $2499.99 89%
$2500 to $4999.99 91%
$5000 to $9999.99 93%
$10000+ 94%


This is the current formula:
=IF(N9<=$B$9,$F$9,IF(N9<=$B$10,$F$10,IF(N9<=$B$11,$F$11,IF(N9<=$B$12,$F$12,IF(N9<=$B$13,$F$13,IF(N9<=$B$14,$F$14,IF(N9<=$B$15,$F$15,IF(N9>=$B$16,$F$16,IF(N9<=$B$17,$F$17,IF(N9>=$A$18,F18))))))))))*N9

Here is the link to the spreadsheet - Please let me know your thoughts on the best approach to this or feel free to edit it. Thank you in advance!!

docs.google.com/spreadsheets/d/1ZKZcqZn0cbrYNerYpcSn8uTcz49EJsgqpFNtkjh0hKo/edit?usp=sharing