If they're aggressive hagglers and you get a feeling they're trying to stiff you, whack a stupid price in and don't think twice about walking. You don't need them, it will be a nightmare, you will lose.
But not all Indian restaurant owners are like that, some are reasonable and pleasant. OK it's fair to say that amongst all of our types of customers, the ones we're most likely to get haggled on are Indian restaurant owners, but as Phillip says it's a cultural tradition - quite good fun to play along with actually, as long as you've set your price double your normal rate to start with
It's all about gaining trust and respect. Once you've done a great job at a price that suits both of you, and you've proved to them that you're genuinely trying to do your best for them, they will moist likely keep using you and yes the knock-on to other restaurants and homes of owner & staff is there to be had. And more fun haggling
Presuming it's greasy (as if you have to presume) Powerburst + oxidiser at nuclear strength, as much of it as the carpet can stand, as hot as you can get, scrub 7 bells out of it with a rotary and then the hottest rinse you can muster
Shaun has made the most important point though, you don't want to own a shrinker so make sure you know what you're working on and how well it is fitted, especially door bars.
You can't call yourself a carpet cleaner until you've taken a lingering curry smell home with you, engrained into all your gear, and lived with it for the next week
Have fun
