How much was the hotel they all sem a dear do and lt looks cheaper to fly there than go by train
Check train fares on National Rail Journey Planner. It would be a challenge to get there and back in a day for a reasonable fare.
If you could catch the 17.22 back from Bournemouth, then two single tickets would come to £86.50. But catch the 17.45 back and it goes up to £113.50 for an off peak return.