JRPass

How to purchase single leg train tickets

Hi,

I am travelling to Japan in July for 2 weeks. I have looked into the cost of a 7 day JR pass versus individual train tickets for each leg of our itinerary and it looks as though it may be cheaper to buy individual tickets.

Please can someone advise regarding the following: -

1. Can tickets be purchased in advance from the UK? and If so how do you collect these?
2. If tickets are purchased when in Japan do the cost of the tickets increase closer to the departure date (like it does in the UK)?
3. Do train prices vary depending on the time of day (ie. around rush hour)
4. Are the tickets refundable and are there any other considerations or additional costs?

Any other information to assist will be appreciated.

Many Thanks