The books and subscriptions are personal expenses. You don't have a business that buys houses, you have a passive activity.
Per the IRS, In most cases, the expenses of renting your property, such as maintenance, insurance, taxes, and interest, can be deducted from your rental income.
Unfortunately, unless you are a Real Estate Professional, the cost of researching a new property is not a deductible rental expense. These expenses may be considered acquisition costs to be added to the basis of the property, should you buy one.
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