What I would like to know is there are different coloured spots on the files I would like -- green and yellow.
Green means there is unrestricted access; yellow means there is restricted access. This isn't always as simple as where the item is stored.
Am I right in thinking that there are some of these files kept on site -- the others I would have to request for a certain day.
Yes. Quite a lot of the material is stored elsewhere and if you don't order it in advance you may not be able to see it.
Could someone confirm that I must take photos and proof of identity
Yes. You need to take passport-type photos plus at least one proof of identity (passport or driving licence with photo) and also a separate proof of address, such as a recent utility bill, or if you didn't use your driving licence as first ID, you can use it as proof of address.
Finally does it cost the same as access to NRH ?
There is only a charge if you want to print or photocopy something. But there is no facility to save anything to a memory stick, or at least there wasn't last time I was there.
You need a reader's ticket to use the online pre-ordering system, but if you don't have a ticket and you want to be sure of seeing what you want, e-mail them explaining that you don't yet have a ticket, but will be arriving on such-and-such a day and giving them a list of the things you want to see, then they will probably be happy to arrange to get them in for you. E-mail address is on their web site.
A lot of their material is available in digital form - notably the Kirk Session minutes, many of the Free Kirk baptismal registers, abridgments of sasines from 1780 to the mid-19th century, and some valuation rolls, wills to 1926, soldiers' wills and various other stuff. The calendars of confirmation from 1927, indexes to services of heirs, the pre-1780 abridgments and some other material is available in book form without pre-ordering.