What is the ruling on housing ownership contracts for employees which stipulate monthly installments and do not permit cash payment?

It is permissible to stipulate in a sales contract that the price be paid immediately (spot) or deferred for a single term or multiple terms (in installments). This is a valid condition that must be fulfilled, because conditions related to the interests of the contracting parties, such as the term of payment, are permissible and must be fulfilled by the consensus of the Ummah. A company may have a legitimate purpose in selling goods to its employees in installments, such as investing its funds or being lenient with them. This condition is valid and does not contradict the essence of the contract.