Cost: Mortgage Loan in Accouting for Bijberoep

Hi,

I am wondering if i include the part of the interest i pay from my home loan as a cost in my bookkeeping, would there be a disadvantage when i sell my home with the taxes? I have a bijberoep and i do use the homeoffice sometimes, so i am wondering if i can bring it as a cost without any tax implications when i sell the house. I use this office for my day job and for my side job. The article proposed office area/ home area for percentage. Would i need to change this because i would use the office for my day job as well? I read this article, but i am still missing a bit of information. https://dexxter.be/hoe-verwerk-je-je-hypothecaire-lening-in-je-boekhouding/

Thanks,

Öncü