Spend on
the good bits.

Spain uses the euro. Cards are widely accepted, and ATMs are common in visitor centres, but neither fact is a reason to rely on one payment method. Keep a modest amount of cash for small purchases and a separate backup card if possible. Check your own bank’s withdrawal and foreign-currency charges before you travel; the amount displayed by an ATM may not include every fee from your bank.

When a machine or terminal offers a currency choice, pause and compare the terms rather than accepting automatically. Retain receipts for larger purchases and track the currency in which you were actually charged. A planning conversion is not a guarantee of the rate on your statement.

For accommodation, compare the same dates, occupancy, room type and cancellation conditions. Check which taxes or local charges are included or payable separately. For transport, include bags, port or airport transfers, parking and any required equipment. The lowest headline can become a different purchase once the missing pieces are added.

Record whether each figure covers a person, a room, a car or the whole group. Split shared costs deliberately, and keep paid amounts separate from outstanding balances. In the Diary, an estimate should stay an estimate until a provider or receipt gives you the actual amount. Do not count a deposit again when entering the remaining payment.

Choose a few priorities before cutting costs everywhere. Staying longer in one base can reduce repeated transfers, while an earlier reservation may give you more choice. Keep a change-of-plan reserve instead of spending the entire budget before departure. Tipping is voluntary in Spain; decide it from the service and your own preference rather than treating a fixed percentage as a compulsory national charge.