Making money doesn't oblige people to forfeit their honor or their conscience. (Baron Guy de Rothschild)What is the maximum loan amount? --> 2 simple rules

I've got a great ambition to die of exhaustion rather than boredom. (Angus Grossart)

1. The debt-to-income ratio

This rule implies that of your joint net income one third can go to (all) loans. By the term "loans" we understand all loans that are currently being paid (e.g. car loan, mortgage loan main residence, ...) plus the amortization of the new loan.
Maintenance allowance (by the state) can' be taken in account, possible incomes out of constant rental, alimony and other benefits also can if proven. Holiday rental fees (season only) are not taken in account.

You make a living of 3000 EUR net a month and your partner 2200 EUR, which makes a total of 5200 EUR net a month.
One third of 5200 = 1.733 EUR: this is the amortization allowed to pay every month (for all loans).
In recent years some of our partners are more felexible and allow amortizations up to 40% of your net income. In the same exemple that would mean a maximum amortization of 2080 EUR p.m.

If you now take a look at DefA's best rates you will see that this corresponds to a loan of +- 300.000 EUR on 20 years.
Keep in mind that this is the amount you can borrow, which is not the same as the purchase price of the house. Because if purchased at 300.000 EUR you will have to pay additional registration and public notary fees (7% France 12% Belgium) (costs for Belgium).

Calculate your maximum amortization:
My net income a month: -EUR
My partner's: -EUR
Existing monthly payments: -EUR
Our maximum amortization (1/3 rule): -EUR
Our maximum amortization (40% rule): -EUR

Your legacy should be that you made it better than it was when you got it. (Lee Iacocca)

2. Your financial past

If you want to be considered for a mortgage loan at DefA's best rates, then you can't have had serious financial problems in the past. Therefore your name may not be registered in the files of the National Bank of Belgium (NBB) or the "Beroepsvereniging Voor Krediet" (BVK).