You can deduct mortgage interest for any year you pay interest, if you meet the other qualifications.
You can deduct property taxes for any year you pay property taxes, if you meet the other qualifications.
You can claim credits for energy efficient improvements only in the year the improvement is placed in service (installed, turned on, fully operating.) You claim the full cost of the improvement in the year the improvement is installed, even if you are paying over time. (If you later stop payment without paying off the loan, you may have a taxable situation in the future.)
You can deduct home office expenses for any year that you have a qualifying home office, assuming you meet all the other requirements.
You don't report or claim just the fact of buying a house, although you might have some of the other expenses above. Most closing costs are not tax deductible, but instead they add to the cost of your home and may reduce the capital gains when you sell.
You report the sale of your home in the year you actually sell it. You pay tax on the capital gains (increase in value) with certain qualifications and limitations. If you are holding the mortgage yourself and the buyer is paying you over time, you report the installment sale (taxable interest and capital gains) for every year of the installment contract until it is paid off.
