book in advance .... I can get tickets to london for as little as £8.60 at times just needs a bit of flexibility and off peak travel. Sometimes its cheaper to travel a day earlier and stay in a cheap hotel overnight rather than travel during the peak
I can travel from Plymouth to London for as little as £18...but I think I'd need to book at least 2 weeks in advance. I booked about 4 days in advance last time I went,and it was £33 each way.
depending on time of day, a cheaper journey is available via London.
This may be even cheaper if you price each leg separately, particularly if you choose to undertake the London-Birmingham leg with either Chiltern or LondonMidland (although the journey takes longer)
depends how far in advance you book. We're off to Wales in June and I've noticed if I book 2 months in advance its 102GBP - if I turned up tomorrow it'd be 102GBP. If I book 6 weeks in advance its 38GBP. A month in advance is 48GBP. Theres a sweet spot, its getting to know the pattern.
Sorry for lack of pound sign - damn American keyboard!