Could I get some recommendations for an AC Repair Company in Spring.

I recently bought a house and the AC has had issues working a month after I moved in.

I think the sellers "fixed" the issue by setting the fan speed to it's lowest setting, so the registers would read cooler even though the house is note being cooled effectively.

There seems to be a leak in the evaporator unit as the drain pan is full of oil, I think it's probably near a low spot in the liquid line that is badly corroded.

I was hoping to get the leak repaired and recharged, but I know most places I call will want to quote $20K for a full replacement.