Here's a summary of the current regulations:

• Spanish law establishes limits for cash payments in real estate transactions.
• Previously, the limit was €2,500 for transactions involving at least one professional party. It has now been reduced to €1,000.
• Fines of 25% of the cash amount exceeding these limits are imposed, but this can be reduced to 50% if reported within three months of the payment.
• Up to €99,999 can be paid in cash without prior notice, but for amounts exceeding €100,000, notification to the Commission for the Prevention of Money Laundering is required.
• If the buyer is a natural person with tax residency in Spain, the seller can receive the money in cash, but must retain documentation for five years. It is important to take additional precautions, such as having a witness present during the transaction.