Besides fewer features, one of the biggest downsides of buying a Mahindra XUV 700 over the XUV 7XO would be the resale value down the line - the latter will command a stronger price. However, the ongoing discounts on the XUV 700 are likely to negate the lower future value to some extent. Also, if you plan to retain the car for a long period of time, 5 years or more, then resale value becomes less of a deciding factor. So, if you like the XUV 700 and are getting it at a solid discount, go for it.

While the XUV 7XO's third (passenger) touchscreen, new sound system and some other cosmetic enhancements are smaller enhancements over the outgoing XUV 700. But its new dampers with the hydraulic bump stops significantly elevate ride comfort. The latter itself is a strong enough reason to pick the newer version.

Since you are able to purchase a new Kia Seltos or Carens Clavis EV, we would suggest you not look at a used Tata Harrier or XUV700, as these are quite close in size, performance and features. If you are buying used, it makes sense to get something from two segments above. 

As to your query about a diesel or electric, yes, both are not likely to have a high resale value. There's certainly a cloud over diesel's long term future, and the pre-owned EV market is too nascent to judge future potential. 

We would, however, recommend the EV as you will be keeping your car for about 10 years, and in that time with your running you would save on fuel bills. Between the Hyundai Creta electric and the Clavis EV, we would suggest the Kia as it's very similar mechanically. But also offers you the benefit of the third row of seats, which is quite spacious and usable. 

The Mahindra XUV 7XO is a good option to consider. It is spacious, comfortable and has a smooth ride quality. The XUV 7XO comes with trick new 'Da Vinvi' dampers and hydraulic bump stops. This elevates its ride comfort above the older XUV700. The 2.0-litre turbo-petrol engine is refined and has a good amount of power at 203hp, and the 6-speed torque converter automatic gearbox is smooth.

The XUV 7XO is well equipped with safety features like multiple airbags, ABS with EBD, electronic stability control, hill hold assist, Level 2 ADAS features and more. The top-spec AX7 Luxury variant also gets features like a panoramic sunroof, a 360-degree camera, three 12.3-inch touchscreens, connected car tech, ventilated front and middle row of seats and much more. 

Although the Mahindra XUV 7XO is yet to receive a safety rating. But the older XUV700 had received 5 stars in the Global NCAP crash tests back in 2021, which bodes well for the XUV 7XO too.

Given your requirements, the best option would be the Mahindra XUV 7XO. It has recently been upgraded from the XUV 700 and comes with a host of changes and updates that make it a very strong contender. 

The feature list is expansive with tech that is not even seen on high-end cars, the petrol engine is punchy and enjoyable to drive, the handling is stable, and the ride quality is excellent. 

Being a full-size SUV, it is quite practical too, with a big boot and lots of storage in the spacious cabin. Outings will be effortless and enjoyable, and it is high on safety with active and passive tech to help you all along. 

Unfortunately, there are no sedans in the Rs. 30 lakh range. So, you will have to settle for an SUV, which has some good options. 

The SUV that will suit you best is the new Mahindra XUV 7XO, which is the facelift of the XUV700. 

It features new enhancements, including a three-screen display and a suspension that has significantly improved the car's driving dynamics. You can opt for the petrol automatic, which comes with a powerful 2.0-litre engine. It makes both city and highway driving easy, but it is quite heavy on fuel.

 However, given your limited running of around 12,000km a year, it won’t make a major dent in your pocket.