I'm happy to use the possible figures that a new bus station will be £15m and refurbishment will be £22m. (Though I dispute the costing claiming that refurbishment costs 80% of the cost of a new bus station per square metre!).
However!
For the claimed difference of £7m you get the following:
- A multistory cark park instead of a flat one
- 1,000 sq m of internal retail space (rough estimate, increase if you think the bus station is even more oversized!) paid for as part of the refurbishment
- 8,000 sq m of land saved by not building a replacement surface car park (since there is a car park on the bus station).
Now I know the area is run down and underdeveloped now, and that the land is virtually worthless (it already has a lot of car parks which, of course, undermine the viability of the bus station car park). But, if you have any belief that the area can be generated and the land built upon, attractive more traffic, you should acknowledge that the refurbishment is better value for money.
If you don't believe the car park can be viable or you wish not to attract more car traffic (I agree), then convert it into retail space, a nightclub, office space a museum!
If, and only if, you see the area remaining in its near derelict state for the next 40 years, then I of course agree with you that a new bus station is better value for money.