"It's a capital raising exercise ... It gives Vicki and I the opportunity to look for some more parks we can bring up to a Top 10 standard."
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The standard is high. The Waihi resort has a 25m heated swimming pool, gym, spa, sauna and pizza oven. It received a New Zealand Tourism Award in 2007, and is rated a 5-star holiday resort by Qualmark.
The much-loved resort is arguably the oldest holiday park in the country, opening in 1899.
Heavily involved in the Bay, Mr Smith was the director of the board of Tourism Bay of Plenty, the former chief fire officer at Waihi Beach volunteer fire brigade, and chairman of the Waihi Beach Cycle Trails Charitable Trust.
Also the chairman of the Top 10 Holiday Parks national board, Mr Smith said he'll now concentrate on expanding the business into new areas of the country.
He and Vicki will keep the Beachaven holiday park they own just down the road, and continue to live in Tauranga.
"We won't leave the Bay of Plenty. We love it, it's home to us."
Mr Smith said the holiday park feels like a community - and everything that happens in a community happens in a holiday park.
"Whether it's people finding love for the first time, or people that come in and say I was conceived on that spot ... [to having] to deal with a number of people that have died in the park.
"It's the whole cycle of life. The full range. You see everything - the good, the bad and the ugly."
Jan Butler, 56, has been going to Waihi Beach park since she was born, predating the Smith-ownership by 35 years.
"It's changed hugely [in the last 20 years] ... I couldn't imagine it actually with him. He's made a huge difference," she said.
Ms Butler said Mr Smith goes above and beyond the role of owner.
"He's made it more than just a camping ground."
Maree Brown from Morrinsville has had a permanent caravan at the park since 2008. She said rolling into the park to start a holiday or a weekend away "is an absolute joy".
"I love the camp with all my heart. It has a beautiful complex all around it, and it's so close to the beach. It's bliss - true bliss," Ms Brown, 52, said.
She said Ian and Vicki have put their heart into developing the grounds, the facilities and the atmosphere - and it shows.
"[Ian] calls it a resort and it really is. It's rather beautiful."
Mr Smith said the highlight of the 21 years was getting to know hundreds of people.
"The people absolutely make it. We've just had some fantastic people come to stay with us.
"It's part of people's lives. It's shaped who they are as people."