*Strictly distinguish between expenditures and investments: it's very easy to put everything as cost or overhead: don't do this. Apply an easy rule: expenditure or cost is money thrown out of the window - you can't expect any return money on it, while investment is desirable (of course, not every investment is desirable): this should bring you more money, more property able to make you more money - the only questions you should carefully consider are whether you can/should afford such an investment at the moment, how much you're going to get back, how fast and whether it is acceptable.
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