Time to cleanup my Aircon (yoohooo !!!) (Singapore)

Hey Guys

It's been soon 3 months that I am in my fantasticly great apt (true story) and in order to be in good conditions with my Landlord, I need to have a cleaning company to take care of my aircon machines.

Pricing is random in Singapore (from 17$ per aircon if you subscribe a year) to 40$/aircon. I heard stories of companies that intentionnaly break your aircon so that you call them later to repair... etc etc.

Is there people around who do not pay too much but have an awesome ratio price/service to recommend?
With money saved, I'll be able to buy more beers to my buddies, you can count on that :)

Thanks in advance for your advice.

Cheers!

Brian