Is Zakat obligatory on inherited or purchased lands not intended for trade, but rather prepared for housing, or for saving for children, or for future investment?

As long as you are hesitant about the intention to trade with these lands, there is no zakat (definition) due on them. If you intend to trade with them or with some of them, scholars have differed. The majority of them stipulate for them to be considered trade goods that they must come into your possession by your choice and with the intention of trade at the time of acquisition. Thus, there is no zakat on them if they were inherited or if you did not intend trade with them at the time of acquisition. Some scholars, however, hold that merely intending trade is sufficient for zakat to become obligatory.