I think making soapy water would be where it's too much trouble and I call someone.
Depending on where the leak is and how long it takes someone to find it it could end up costing hundreds if not more. You can google some of the cost estimates for doing stuff like this. It's not hard to look for a leak and a lot of the times you'll see the oily residue around the leak.
As for the OP, depending on how big the unit is and what the aims of the builder were, that unit is probably only setup to cool a certain number of degrees below the outside temperature. Say 20.
For most people it's not realistic to think you can cool your home to 68 when it's 118 outside.
Whole house fans are cheap to buy and install. Say ~300, you turn it on in the morning to move in cool air and at night to bring in the cooler evening air. That can help the AC by preventing how long it will run.
Putting a film that blocks some of the heat transfer works and not too expensive.
I went and bought some trees that are pretty decent sized and planted them to block the sun down the road. Just a little shade can do a lot.