An Off Peak Return (SVR) is £119.10 route +London (includes LU).
Restrictions apply Monday-Friday: Valid on any train from Havant to Waterloo and then valid on any train at or after 0905 from Euston.
Return within 1 month, valid on any train timed to arrive into London at or after 1005.
If you travel via St Pancras and Leeds, the ticket is valid but different restrictions apply.
If you travel via Banbury then a change of route excess is required, this is priced at £2.50 each way and is payable either at a ticket office or on board the train.
If you wish to travel cheaper you will need to do one of two things (or possibly both)
1) Book in advance, preferably as soon as tickets go on sale. In general tickets go on sale up to 12 weeks in advance, so mid-June at present. On some routes weekday tickets go on sale a while before weekend tickets.
2) Split the journey into a combination of tickets. Note that if you do this, you have to travel via, and the train must also call at, the station(s) you 'split' at.
Mid-June is a good time to visit Carlisle; you'll get maximum sunlight hours!
You might be able to get a 'Bargain Berth' on the sleeper if you travel at a non-busy day and book far enough in advance. They're available on the Scotrail site and you may be able to find one for £29 or £39 one-way. 'Bargain berths' include the cost of travel and also the use of a twin-berth cabin.
