I had a fairly big fish kill so would like to just finish off the whole pond and start over, it's about an acre. I'm looking for a cheaper way to kill off the remaining fish. Also I'm in a Homes Association

Drain the pond.  Spare the local environment.  There's no way you'd be able to recover without fresh water anyway.

Then try to identify the fish kill... otherwise, it's bound to happen again.

Welcome aboard, @spoondfed!

Fish die offs happen for a reason and that is usually poor dissolved oxygen levels and or habitate.

Does your pond have aeration pump and adaquate prey source?

Rotenone depletes the DO and the fish suffocate, it's a messy process. Draining the pond may in the long run be a better choice to improve the environment.

Tom

I'd keep poison out of the equation if at all possible. You might be able to contact your DNR and have them shock the pond to remove the remaining fish and possibly even inspect them to see what is causing the die off.