I am in college and learning some database fundamentals with MySQL all information is fake and only setup for teaching.

The objective is to get the total balance from the customer table that has a sales rep whose rate is = to the minimum for all sales rates from the reps. There is a rep table and customer table that I know can INNER JOIN using the rep_num however I am having trouble getting the subqueries right to actually spit out anything.

I am still fumbling my way through learning
Any insight would be appreciated!
rep table containing rep_num, first_name, rate
customer table containing balance, customer_name, rep_num
Initial queries to check information
Initial queries to check information
The query I have worked up to after a couple of hours

I checked the rate column to see what the minimum was and had an idea for what that part should look like and did the same for getting a total balance from the customer table. I originally was doing all subquery attempts till I worked out that an INNER JOIN would be a better setup and then tried a few variations and after awhile I just can’t seem to get it to go through and Give me the display I need.