Need Help Creating An IF Statement

Here's some context to help perhaps make my goal clearer.


If my staff sells a home for under $100K, and the client is there's, then they receive a commission of 3.5% of whatever amount the home sold for under $100K.
Ex--> $100,000 home provides my staff with $3500 in commission.


If my staff sells a different home for the same price, but they're helping one of my clients, then they receive 60% of the regular commission.
Ex--> $100,000 = $2100 commission.


If my staff sells a home for over $100K, and the client is there's, then they receive a commission of 3.5% on the first $100K and 1.5% on anything thereafter.
Ex--> $250,000 = ($100,000*3.5%)+($150,000*1.5%)=$5750


If my staff sells a different home for the same price, but they're helping one of my clients, then they receive 60% of the regular commission.
Ex--> $250,000 = [($100,000*3.5%)+($150,000*1.5%)*60%]=$3450

I want to differentiate between the amount of their commission if the home was sold to my client or theirs.

Attached is the file of what I'm trying to do, what appears to be happening, and what things "should" look like.

How would you create the formula?