Tally with inventory

Dear All,

I am working in a Realty Co. My co. is engage in booking flates in the name of co, and then selling it to the customer/client.  Till the date, flat is not sold instalments are paid by the company. when the sale deal is final we  pass purchase  and sale entry for that flat.

My issue- I want to maintain stock of flat in tally, So, pls guide me on the subject.

Kindly guide me on the matter.