Finding sum in a table but leave cells blank if $0 AND then finding sum of the lowest values in each table

I am working on a spreadsheet for my wedding expenses and am wanting an easy way to track totals of vendors. I have made charts for the individual vendors and found a way to calculate totals as we make payments.

HOWEVER, I am wanting to find a way to get the totals in column C as we pay more in column B, WITHOUT having the totals come out as $0 in the lower rows if no values have been entered (i.e leave those rows blank).

Also, Once I get those rows to be blank if no value is entered, I want to find a formula that I can put in Table 1, that will sum all the lowest values of the tables on the left so that I know my running total left to pay for the wedding.

So looking for 2 equations to get me to what I want. If there is an easier way to do so, please feel free to comment. Just wanting to find the easiest way to get the tables to reflect the totals left to pay AND get the overall total for all vendors. Thank You