Assalamualaikum May i know about unknown unclear about a work . My friend got inherited a land contract document after the death of his parents but useless zero condition land contract neglected for 80 years . Not even know land location where is it . His parents not told anything about that land . Land area is nearly two acre . Tried two times but failed before. And he gave up . After 20 years ,He told me about his lost land and wanted to try ,work and invest with him . So I agreed .I took responsibility to search ,I spent over one year Finding two acre land location in a township 36 square miles area.If location wrong, government will make a lawsuit .A very difficulty and risk work . Finally I found and right area . Government occupied and invaders are there . So we together invest and work to make many legal actions in government offices to get back land or compensation. Win or Lost condition will happen .After five years , we won and government agreed to give compensation not give land . If we get compensation for that land How we two can divide in correct islamic way ?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

The meaning of your statement in the question: “and he wants to try again to search for it, and that I work and invest with him,” is not clear. So, does the contractual agreement between you state that you help him search for the land and recover possession of it, if it were usurped, but you did not agree on a specified remuneration for your services when the task is accomplished and the possession of the land or its value is recovered from the usurper? If this is the case, then you are entitled to remuneration for your services equal to that commonly paid to the provider of such a service, to be estimated by competent experts in this field.

However, if you mean that you bought a share of the lost land or entered in a partnership with him by investing a sum of money in seeking to recover the land or obtain compensation for it, then the contract is null and void, and you are entitled to your capital only.

Allah knows best.