Just mail him the legally required return of the deposit and the accounting statement for what you deducted, along with any necessary invoices/receipts, and be done with it. 

I have heard that those investments provide sizable tax deductions (e.g. 70-100% of the intangible drilling costs are deductible in year 1, and all tangible drilling costs are deductible over a 7 year depreciation schedule). 

You don’t get to deduct the price of the pair of jeans you bought to replace that pair, to sell later.

The landlord first threatened to deduct money from our deposit if the short bushes in the flowerbed died, so I started watering the flowerbed by manually turning on the irrigation system and turning it off ten or twenty minutes later.

Case in point Holiday falls on the first of the month which is a Friday, and their company pays payroll the day after a Holiday which is Monday. expecting payment Thursday would be a bad idea, because that means they pay their rent a near week before payday.I would deduct from their security deposit for fines, tenants are living in a high value asset, they can destroy property confrontation should be avoided.You should take responsibility for pest control its your asset you are protecting.Steep fine for painting, you might as well say eviction, you will never collect that money.Don't restrict your payment methods. 

Unfortunately, I know she is not interested in renting the place out.Another option that I've thought of is that my wife and I could buy the house from her if she were to supply the financing (as we cannot afford a mortgage on that house now) and then we could sell the house after living in it for two years and also get the 500k federal tax deduction.

To consider an allocation to deduct the old roof you would have to do some research under the Tangible Property Regulations that would allow you to break out the remaining life from that portion of the building.

I suspect that right now you want cashflow over things like appreciation and tax deductions.

I also noticed that you put all kinds of deductions in % numbers on your cash flow.

I need to figure out how many years I can legally charge my previous tenant for the carpet replacement and deduct from security deposit.