VBA goal seek multiple cells

Hello,

I want to goal seek several different cells.
First, I want to change cell A1 by setting cell B1 to 0. However, A1 takes into account the value of C1.
Then I want to change cell A2 by setting cell B1 to 0. However, I want the value of C1 to have 5 added to it before goal seeking.

Anyone know VBA for this?