That depends on how you want to wire the strips. If you want to run individual 18AWG wires from each strip to a junction box you will need a lot of wire bro. Probably around 30 feet but that’s a quick guess. I tried that method but you end up with a lot of stiff wires to have to work with.
It depends on your ability cos the above is probably the least technical way of doing it. Now i make busbars out of 12AWG single core with 18AWG tapoffs for each strip but i’ve done electrical work for a long time bro.
Here’s a link to what i’m talking about. I made this loom for 5 strip rigs but it can be scaled up. The busbars are 16AWG which is good for up to 8 strips.