The fare of £36.30
is the best price for a Banbury to Bournemouth Off Peak Return (SVR) with a Railcard!
However it may be cheaper to buy a different set of tickets, instead of a Banbury to Bournemouth SVR.
My standard advice:
"Splitting" the journey into a combination of tickets may work. Use a WebTIS website (e.g.
EC,
LM etc) and click the info (i) button next to the itinerary you want, then tick 'show all calling points', this shows the places where you could "split" the journey into a combination of tickets (note the train must call on the return journey too).
In this case there are not that many stations to choose from: Oxford, Reading, Basingstoke, Winchester, Southampton Airport Parkway, Southampton Central and Brockenhurst.
Note that if you want to return a different day (as in this case), then unless singles are sensibly priced (unlikely in the case of shorter distance singles) it will not be cheaper to split at stations where only
Day Return tickets are available. Therefore, it is
generally only best to look at longer distance tickets, where Off Peak Return (SVR) fares can be combined.
Travelling at "peak" times (which varies by route and ticket held) can be reduced by purchasing tickets with more favourable restrictions and either splitting and/or starting/finishing short. Again, some TOCs do not like this and can take action. However it does not sound like you are going to be travelling at peak times so that won't be relevant in this case.
You can take advantage of
Routeing Guide anomalies by looking for 'over-distance' tickets which you can then start/finish short, though ATOC and some TOCs are keen to remove such anomalies so if they get mentioned here that can mean the end of them. Finishing short/breaking your journey is not permitted with Advance tickets though, so this technique is only valid when using "walk on" tickets, but that's unlikely to be problem as you won't be using Advance fares (there are very few walk-on tickets that do not allow this, on the outward portion, and are unlikely to apply in your case).