Depending on the "Comunidad Autonoma" there's different taxes involved for example in Catalonia ITP (taxes for second hand houses) are 10% and if you are in Madrid are 6%.
I'm currently securing a house in Spain and wanted a method to compute monthly payments, so I created a tool for it (despite knowing Excel could suffice, I enjoy making things).
I'm considering adding features such as:
Bonuses: Interest reductions from banks for bundling services (like home security, insurance, etc.).
Visual charts
An amortization schedule
I'd love to hear your suggestions on what to include next.