Buying a home is an exciting experience, especially if it's your first time. However, it can also be quite complex if you’re not sure where to begin. When you need a mortgage to make the purchase, it's important to understand several key factors from the start.

The first thing to know is how much the bank is willing to lend you. Today, most banks finance up to 80% of the property’s value. Some may go up to 90%, and a few can reach 100%, although this is rare. Therefore, you’ll need to cover the remaining amount and also set aside an additional 10% for taxes, notary fees, property registration, and other purchase-related costs.

Before approaching the bank, it’s a good idea to conduct an honest review of your financial situation. You should be clear on your net monthly income, fixed expenses such as current rent, loans or insurance, and how much savings you have — especially for the down payment and closing costs. It’s also essential to make sure you’re not listed in any credit default registers like ASNEF and to have a realistic budget in mind for the home you wish to buy.

To request a mortgage pre-assessment from the bank, you’ll need to provide some basic documentation. This includes a valid ID such as your passport, NIE, or DNI. You’ll also need to show proof of income. If you are employed, the bank will typically ask for your last three payslips, your employment contract — ideally permanent — and income tax returns from the past one or two years. If you’re self-employed or a business owner, you will need to provide VAT and income tax declarations for the past few years, along with Social Security records and, in some cases, accounting books.

The bank will also request your bank statements from the last three to six months to assess your income, spending habits, and regular transactions. If you’ve already chosen a property, you’ll need to provide information such as the address, purchase price, whether it’s a new build or resale, and seller details. A simple registry report might also be needed to check if the property is free of liens or previous mortgages — though sometimes the bank will request this directly.

Additional information may include your marital status (some banks require a marriage certificate or details about your marital property regime), number of dependents, and any existing loans or debts like credit cards, car loans, or personal financing.

During the pre-assessment, the bank will evaluate your repayment capacity by comparing your income against your expenses and other debts. Typically, your monthly mortgage payment should not exceed 30 to 35% of your net income. They will also check your credit history, ensuring you have no missed payments or outstanding defaults. Employment stability is another important factor — permanent contracts or a consistent income as a self-employed person improve your chances. The bank will also assess the property by carrying out an official appraisal to ensure its value backs the loan amount.

Before committing, it’s important to have a clear idea of the type of mortgage that suits your profile. A fixed-rate mortgage offers a stable monthly payment, giving you long-term security. A variable-rate mortgage often starts off cheaper, but the payment can fluctuate based on the Euribor rate. A mixed mortgage combines both: a fixed rate for the first few years followed by a variable one.

Keep in mind that requesting a pre-assessment doesn’t bind you to that particular bank. It’s wise to compare several offers and conditions. Pay attention not only to the interest rates — both nominal (TIN) and annual percentage rate (APR or TAE) — but also to fees such as opening costs, early repayment charges, or subrogation fees, as well as any required linked products like insurance, salary deposits, or credit cards.

Being informed and well-prepared from the start will help you make sound financial decisions and bring you closer to the home you’ve been dreaming of.