Deductions & credits

Thank you so much for the reply.  My mother passed away before my father, so I am using the city assessment done the month and year that he passed as the cost basis.  I was unaware that improvements were not deductions but instead to be added to the cost basis - but that makes sense.  Does it matter that some of the updates to the property were paid for a few months before he died? Or am I ok to include those since I have the receipts for the work and the house was technically in my name?  This is very helpful - thanks again!