Therefore, it is sufficient to forgo its mention, similar to an absolute price in a land where a known currency is used, [and the variation in residence is slight, so there is no need to define it]. What he mentioned is not correct, for the harm hardly varies by the number of those who reside and their fewness, and it is not possible to define that. Therefore, reliance upon customary usage (urf) suffices in this matter, just as in entering a bathhouse and the like. If he were to stipulate what he mentioned, it would be obligatory for him to state the number of residents, and that no guest, visitor, or anyone other than those he mentioned should spend the night with him, and he would have to know the description of the resident, just as he knows that when he leases for the purpose of riding.

Section: If one leases a mount (riding animal) to ride it, he may have someone who is its equal ride it, or someone who is lighter than him, but he may not have someone heavier than him ride it. This is because the contract entails the realization of a benefit measured by that rider; thus, he may realize that benefit himself or through his deputy, and he may realize less than it, because he is realizing a portion of what he is entitled to. However, he may not realize more than it, because he does not possess rights beyond what he contracted for. Equality in height, shortness, or riding skill is not stipulated. The Qadi said: It is stipulated that he be his equal in all these qualities, because a lack of riding skill puts a burden on the mount and causes it harm. The poet says:

They did not ride the horses until they had grown old... so they are heavy on their backs and rough.

Our position is that the variation in these matters, once equality in weight is established, is slight and thus excused. This is why its mention is not required in the lease contract, and if it were to be considered, his proficiency would have to be stipulated in the lease, just like weight and lightness.

Section: If he stipulates that he shall not realize the benefit through anyone equal to him, nor through anyone lesser than him, then according to the reasoning of our companions, the contract is valid, but the condition is void.