Can anyone please guide me based on above?

I'll try to put my inherent dislike for most so called "premium brands" to one side and be objective about your two choices.

And in all honesty, it is not difficult due to this being a family car!. Why would you contemplate a 3 Series saloon (rather than estate) as a family car?. So IMO it obviously has to go, leaving the X1 out of those two.

So I am leaning more toward X1 as I believe it will hold its value better

Curious to learn why you think the X1 will hold its value better than a 3 Series?

and might be more practical.

No might about it, the 3 Series is a 4 door saloon and the X1 is a 5 door SUV, so it is more practical.

Also advise which of these car have lower running costs?

Can't imagine there would be much difference in running costs as they both use the same engine (albeit in a higher state of tune for the 3 Series).

Finally, and this is very important. What mileage do you cover per year and what type of journeys?. Because if you are doing less than at least 12k, predominantly on faster roads, getting a diesel is not very wise at all.

I am after my first family car .........I have narrowed down my search to a saloon or a small suv.

Too narrow. Excludes the obvious choice - an estate car. Families need lots of space.

Also I would like to experience premium brand for first time hence I am really keen on a BMW.

Oh dear. On your budget, I think that might be unwise. (You may have heard the quip 'BigMoneyWorries'). Families tend to consume much of the household income for non-motorng items and services, so the less spent on cars the better. I would search for mid-size estates from Ford, VW or reputable far eastern makers.

Edited by SLO76 on 23/04/2023 at 22:14