"From conceptualizing the idea to launching 3Q, it took us 4.5 months to open one in Shanghai and one in Beijing. Both filled up immediately," she told CNBC.
SOHO 3Q will expand from less than 1,500 desks in both cities, to more than 10,000 desks by the end of 2015. Zhang says the future is to expand beyond both top tier cities.
Zhang has been named one of Fortune's 25 Powerful Chinese Women in Business in 2013 and 2014 as well as one of Forbes' 100 Most Powerful Women in the World for the past three years.
Her rags-to-riches story is also well known internationally but it wasn't without challenges. She recalls an incident in the early days of launching the company.
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"One day when we were about to launch a building, we had our entire sales team headhunted and they all left. So we opened the doors, launched the building with zero sales staff," Zhang said.
Working with her husband was also a challenge as Zhang said they had different ideas and in the early days, they took their conflicts from the office to the home. They've since divided the work, with Pan focusing on public relations, government relations and sales while Zhang focused on managing talent and finances.
On the Shanghai stock market, Zhang says like everyone else, she is worried when prices go up so quickly. Zhang's SOHO China listed on the Hong Kong Stock Exchange in 2007 and while she has considered a listing on the Shanghai A-share, she decided against it.
"You can't run your company on these arbitrage opportunities. I think about what would be my long term, sustainable capital source and still getting access to international capital markets is important," she said.
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The slowing Chinese property market doesn't worry Zhang however, as the company is focused on commercial property in the prime locations in Beijing and Shanghai. She thinks the current slowdown hurts developers who are focused on residential developments in second- and third-tier cities.
The economic environment is a crucial part of what many entrepreneurs say are the challenges of doing business in the mainland. Zhang says her one piece of advice to entrepreneurs looking to build a business there, would be to avoid the traps of short-term success.
"China is a market that has a lot of short-term temptations and this is where entrepreneurs easily fall - short-term success but something that doesn't give you the long-term future. Remember that you're in this for your life, not for tomorrow," she said.
-- For more on Zhang Xin's interview, tune in to Entrepreneur Asia: Power Players on CNBC. The episode will air on June 4, at 5:30pm sin/hk, with repeats over the weekend.