I recently heard, 如果你不介意 (literally: "if you do not mind."). Is the literal translation from English also a correct, native one? Or is there a more common way to prefix such a question?
Only very very polite person would say "如果你不介意 (if you don't mind)", probably this person is very well educated which is rare in China (school/parents simply never teach you this phrase). But interestingly, from my experience I sometimes speak this kind of language to my close friends, to make fun of him/her, in this context, when I say "如果你不介意", what I really mean is that you have to do whatever I am asking for...
I've spent some time in both Taiwan and the Mainland. From my experience, I've heard:
在乎 zai4 hu 在意 zai4 yi4 管 guan3 - More Mainland style... "我不管!" 无所谓 wu2 suo3 wei4 - A really popular phrase to show that you don't really care/mind 随便 sui3 bian4 - kind of like "eh, whatever... I don't care".. Also quite popular
But I've also heard 介意
And if you're looking for that native, colloquial flavor, you can throw in 的话 at the end of 如果, which is just an extension of "if".
And what do you mean by "Is there a more common way to prefix such a question?"?
As far as I know, it's the most common way in the area I'm from. In fact, I've never heard anyone phrase it differently.
如果您能迁就的话... 如果您不嫌弃的话... 您能将就的话...
Usually we don't say '如果' in oral Chinese for this case.
I don't feel it is a native expression in Chinese. It probably is influenced from the western culture. On rare occasions I hear people use it, but it still feels strange as an oral phrase.