1. You must be authorized by the author, but you don't have to come forward yourself. You can also contact each other through domestic publishing houses. It must be rice. Whether there is a market or not depends on the contents of the book itself and the market expectation in China. It is possible from tens of thousands to hundreds of thousands, and the details can be discussed with each other, but tens of thousands of dollars are definitely needed.
2. You can try to search online according to the Chinese translation of the book title or the author's name, or you can contact the other publishing house by email and ask whether the copyright of China Simplified Chinese characters has been sold.
3. The publishing cost of sci-tech books is generally quite high, mainly because the expected market is small.
I don't know which book the landlord is. Please email me if you are interested, xpbook @139.com.