Actually, he's right that most 2007 - 2009 models are driven above 70K. The ones which are 50k on ODO are very hard to find.
But you can find a Passo 07 1.0L clean in your range for sure. I've neither owned Alto nor driven it bro so can't say anything on Alto BUT yeah one thing, Passo surely got better grip then Alto. But then again you'll be getting Alto which is newer as it'd be 2011 model.
And an 1000cc engine is always better when compared to 660cc. Keep in mind that if you get harsh on accelerator than a 660cc would give you less mileage THAN 1000cc. As you'd be demanding more power out of a small engine hence it'll require more fuel to burn to reach the car's speed at your desired level. So this is how it works. However, in normal circumstances it is true that a 660cc would give you better mileage than 1000cc.
And IMO, 1000cc is a better choice.
My Passo which is 2008 and was driven 83000KM. And you couldn't tell by looking at the car upside down, engine bay and every single inner and outer corner that this car is even driven 10K ALTHOUGH It was driven 83K. So don't rely on tempered meters if you find a car very clean. Because 95% JDMs are tempered.
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