You need to find the loan documents. They will control. Typically, the note or another document will state that in the event of a death of a...

We were promised a/c by September 1 in our lease but its at the end of the month and still no a/c what are my rights??

You need to document, in writing, what has and has not ocurred. First, send a certified letter indicating that no A/C has been installed. ...