Inventory is the total amount of those commodities which are in one’s possession for the purpose of sale. One must total his inventory at the end of the year, and 2.5% must be paid from its value, whether its value was equal, greater than, or less than its price. Samurah, may Allah be pleased with him, narrated: "The Messenger of Allah, peace and blessing be upon him, would order us to give Zakaah for our commodities which we own in order to sell (to trade with).” (Abu Dawud).
Some examples of commodities which are included in this ruling are as follows:
1. Land which one buys and sells,
4. Machines which lift water,
5. All other commodities which one owns in order to sell.
As for the buildings which one owns and gives out on rent but does not sell, Zakaah is due upon its rent, if it is in his possession for a year (after having reached the nisaab). As for its value, there is no Zakaah upon it, for it is not owned in order to sell.
Also, there is no Zakaah on one’s personal cars, or taxis, either (or rental cars), if they are not owned in order to sell, for the owner only purchased them for their use.
If the taxi owner (or rental car owner) saved an amount of money which reaches the nisaab, he must pay Zakaah upon it if a year passes and it is in his possession, with disregard as to why he saved it, such as daily expenditures, marriage, purchasing land, returning a loan, or anything else. This is due to the generality of the legislative proofs indicating the obligation of Zakaah in the likes of these cases.
Also, the correct stance from the statements of the scholars is that one is not excused from paying Zakaah if he is in debt, due to what we mentioned above.
Zakaah must also be paid for the wealth of orphans and the insane, according to the majority of the scholars, if the amount has reached the nisaab and it is in their possession for the period of one year. The guardians must pay it on their behalf after the completion of one year due to the generality of the evidences, such as the statement of the Prophet, peace and blessing be upon him, in the hadeeth of Mu‘aadh when he sent him to (teach) the people of Yemen: «» (Abu Dawud).
: Alssunnah Net