I've valued a rugby facility in my local town. The way I approached it was to say that if they wanted to replace this facility what would they have to pay for land, and I judged that they would likely to look to buy level, well drained agricultural land on the edge of the town. I was fortunate that there had been two or three recent sales of blocks of land like this, along the town boundary over the last few years, so comparables were available.
I was also fortunate that I didn't need to value the pavilion as that was owned by the club. I've valued pavilions in the past for local authority, accounting valuations and generally valued them on a DRC basis.