Given a travel related situation, and given a specific question about the situation, summarize the question into a title

Q: The official UK document says: 


  You can bring in other goods worth up to £390 (or up to £270 if you arrive by private plane or boat).
  
  If a single item's worth more than your allowance you pay any duty or tax on its full value, not just the value above the allowance.


The question: 

Is the tax-free allowance applicable per an individual item or per total cost of all items combined in a baggage?

If you need a more detailed example, here it is. 

I am relocating to the UK and going to take my desktop computer with me. I want to disassemble it and put small parts into my backpack and big parts into a suitcase that will be put into aeroplane's luggage. All these parts will be with me upon my arrival to the UK.

As for the computer. I bought all its components separately in my country and put them all together and used the computer for around a year. Almost all the parts in the desktop were cheaper than the tax-free allowance except the Video Card.

What will I be charged for? For the sum of all the components prices or only for the video card? 


A: Is the tax-free allowance applicable per item or per total cost of all items combined in a baggage
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Q: Besides the Turkish Lira, can I use US dollars and/or Euros in Istanbul?

I mean particularly for paying in taxis, groceries and vegetable markets.

If this is possible, is there any additional cost for this? I.e. will I pay more if I pay to a taxi driver in US dollars?


A: What currencies can I use in Istanbul?
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Q: I'm currently enrolled at Victoria (by TAP). Even though I collected new miles over the holidays, my old miles will expire. 

What other Star Alliance programme would extend the expiry date of all my miles without extra charges? 

Note that this is the case with FlyingBlue (by KLM): my miles would expire in February, but with the new miles I collected over the holidays, all my miles have a new expiry date. Thanks.

EDIT: This list shows a number of airlines that allow free resetting of expiry date, although it doesn't split the airlines by alliance.


A:
Star Alliance programme with free expiry date extension
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