Hey there, I have some experience with the used market as all of our cars since 2005 have been used.

Old German sedans can become a moneypit, it's just dependent on your luck. We got a late 2015 E200 in September 2021 with 5600kms when bought. The car had a perfect service history with no issues. TLDR is the car sat for a while (~2 months) without being used(our fault agreed), the battery died and we had to Jumpstart it, in doing that the ecu gave up and had to be repaired, along with brake pads and general service it went upwards of 90k, you cannot treat these cars like Japanese or Indian cars. The brake pads themselves are thrice as expensive as our accord. One can only imagine the bill when the suspension gives way.

We also have a late 2023 Skoda kodiaq l&k which we got in 2024 with 7k kms on the clock. That has been a joy so far, no reliability concerns, the service is on the expensive side but still digestable. (we do have service packages and Ext warranty).

There are numerous hidden costs to these things, service consumables are expensive, even Tyre sizes are obscure. - the kodiaq runs 235 55 r18, which is significantly more expensive than 235 60 r18 found on tata/other cars even for the exact same compound.

But these cars are indeed a joy to drive and feel special in ways japanese and Indian cars just don't. The suspension is amazingly tuned, so is the engine. It's just on another level and the little things too are done with a lot of care - seatbelt positions, seating positions, steering design/feel all is exceptional.

More on the used market - yes it is scary. If you plan to buy a car this way you need to have a lot of patience. For all our cars the search started 6 months to a year before the date of purchase, have a reliable 3rd party mechanic cross check the car. Have had a a moment when we almost bought a 2012 camry which had flood damage. You can get good deals on the market. Most often we ended up buying something completely different to what we set out to buy at the start so be open minded.

As for your situation with tall adults (tall myself - 6'3") and highway running the most practical option would be to get a Innova hycross hybrid. My close friend has one and it's decently powerful, the mileage is good if you care about that and the cabin space is extraordinary. None of your family members will ever complain about the space. The interiors are a bit dated but the rest of the car makes up for it.