Excel nested if condition

I'm trying to write nested if condition using AND, OR, MIN, MAX inside IF condition. but i couldn't solve this below problem.

I have a column with Payments, if that payment is less then 20k then it should take 100% of the payment.

If the payment is between 20k - 40k then need to calculate 80% of the payment but after calculating 80% the result is less then 20k then it should write 20k. if the reslt is more then it should write the result.

if the payment is between 40k - 75k then need to claculate 70% of the payment but after calculating 70% the result is less then 40k then it should write 40k. if the result is more then it should write the result.

if the payment is between 75k - 100k then need to claculate 70% of the payment but after calculating 60% the result is less then 75k then it should write 75k. if the result is more then it should write the result.

if the payment is greater then 100k need to claculate 50% of the payment but after calculating 50% the result is less then 100k then it should write 100k. if the result is more then it should write the result.

I tried writing nested if condition to form one formula using min fucntion and AND operator but nothing is giving the result accuratly.