Maruti Suzuki Brezza Petrol VXi MT

You will have to stretch your budget significantly to purchase the Tata Sierra automatic. For around Rs 12 lakhs on-road, what you can shortlist instead are the Mahindra XUV 3XO MX3 Turbo-AT and Skoda Kylaq Signature AT, both of which are safe, spacious, comfortable, and also get a sunroof. 

The Maruti Brezza is likely to get an update in the coming weeks. Since you are not in a hurry, you could wait and see what it has to offer wait for, before going ahead with the purchase.

The Maruti Suzuki Brezza is a good choice for your requirements. It is a spacious, practical, and compact SUV that is easy to drive in the city. The 1.5-litre petrol engine lacks punch and delivers mediocre performance. But it's smooth and refined and, coupled with a fairly responsive automatic gearbox, does the job for city driving quite well. 

More importantly, the Brezza is easy to get in and out of thanks to wide-opening doors and a comfortable step-in height. 

The Brezza is also a very reliable car, and Maruti's service network is very strong, so you won't go wrong there. The facelifted Brezza is expected to be launched later this year, though we are not aware of an exact timeline. 

The other alternative cars you could consider are the new Hyundai Venue, which is today the best overall compact SUV, or the Kia Syros, which is extremely spacious, especially in the back seat. 

There are not many petrol automatic cars, at any price point, that would do upwards of 15kpl these days. Turbocharged cars, especially, require extremely careful driving to achieve high fuel efficiency numbers, and the automatic gearbox reduces these chances, as the gear shifts are not in your control. If fuel efficiency is your ultimate concern, we would recommend a good naturally aspirated petrol engine, in a small, relatively light car. The Maruti Suzuki Fronx 1.2 petrol AMT is a good option, but its automated manual gearbox is not very smooth, and its engine is not very powerful. As a trade-off, you could also try the Maruti Suzuki Brezza 1.5 petrol AT, which has more power and a smoother torque converter automatic. But will deliver slightly lower - but still very good - fuel economy.

It is very sad that you're having to retire your well-maintained Polo due to the 15-year rule in Delhi NCR. Since you have a budget of Rs 7 lakhs, we'd advise you to get a 2020-21 Maruti Brezza or Toyota Urban Cruiser, both of which are smooth, well-built cars. Their seating position is high, visibility is good, and controls are light, which makes them very user-friendly. 

Also, try finding the newest possible example, which will ensure that you drive the vehicle for 9 or 10 years before it reaches the 15-year age-limit.

For your outgoing car, you could consider getting in touch with used-car platforms such as Spinny; they'll do the paperwork, and should get you a good price.