In doing the research and developing a solid business plan, we would need to look at business models where the masseuses share of the per hour rate is at least 50%, for good masseuses who are certified RMT's and can issue legit insurance receipts. In many of the spas, the receipt is issued under the name of a therapist who may nor even be around, while they take advantage of the masseuses by not paying them well.
On the other hand, if it is only all for fun and games, we could go on a trip to Shanghai and seek out business associates who need large sums of money laundered in the west, and offer our (chain of) massage spas for this purpose. In this case the real financials don't matter as we would always be declaring more revenue than we make (and happily paying a load more in taxes) with the express purpose of delivering clean, post-taxed funds on the other end. Could be set up as a Limited Liability Partnership. However dealing with the triads, longer term could prove fatal. But while alive, would be a boat load of fun.