haha, this sure is 'refreshing' talking about A/Cs away from the usual TVs and Subwoofers here .. ....
My opinion is that for Malaysian standard living room we need at least 2 kudas.
If your living room is those that stretch all the way back to the kitchen (ie, not enclosed area), do not expect artic conditions, just cool breeze.
As for the invertors, if you are looking at it for cost-savings, you need to know that are a few criterias to achieve that, most likely abnormal settings that we do not comply. For 'air-purifying', don't dream, get a seperate full-fledged one. You should also know that invertors a/c have more costly entry and maintenance cost, right?
Air-conditioner recommendations