Hello there,
Just by way of comparison, my cub in Hamilton (Melville United) this year constructed new dugouts for our No 2 pitch. Using club members' and supporters' labour and skills, and donation of materials in some cases, we were able to get two roomy steel-framed dugouts, complete with signage and perspex sides, completed for under $1000. These are heavy, but nominally portable, and designed by a couple of our club members, welded by a mate of a committee member, with fabrication material donated, and signange done by a club sponsor.
The paved area underneath was completed using second-hand pavers recycled from Hamilton Lake walkway upgrade just up the road.
(it looks a bit rough around the edges in this photo with the work still being done earlier on the day of the match).

These dugouts were to complement our more elaborate No 1 pitch dugouts, which we believe are among the better equipped around the northern clubs. They feature fold-down seats with backs, acquired from Eden Park during its refurbishment, and can cater for covered seating for 11 from each side plus a 4th official's dugout. A mural background on fabricated steel combines the benches.

In both instances, there was no council investment, nor, indeed, even any grant funding. But what was encouraging was that once people saw someone had a vision, the buy-in and willingness of club members and others to make it happen was exceptionally good. Indeed, the most challenging bit was probably establishing that initial vision of what was possible.
When the council saw there was no cost to themselves, staff were delighted to assist with something that would improve the amenity value of the park.
As an aside, in 2011 we constructed five terraced seating units for the No 1 pitch, which cost over $50,000. They required engineering plans, resource consent, and ongoing public liability insurance. But they have made a world of difference.
Hope this helps.
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