I categorize all purchases in banking apps/websites that have that built in. I have most of that on a shared account with wife so it's easier. The rest I calcul

I categorize all purchases in banking apps/websites that have that built in. I have most of that on a shared account with wife so it's easier. The rest I calculate in a similar way but in the "not-shared" bank app. As nowadays most of my purchases are card, smartphone or BLIK (widely adopted local payment platform) it's not that hard. Banks also pre-analize each transaction and if they know what kind of business was that, it is pre-categorized as medical/groceries/travel/car/house bills and so on. Overall result is poor - I spend like madman and only recently started to monitor reports successfully. Usually biggest surprises are SMALL purchases, not large ones. Overpaid yogurt in a small local store is fine, done once. But doing that every day, plus add eating out when working from office - this can can be surprisingly costly.