Welcome CVAZQUEZ - you've come to the right place for advice.
There are others more knowledgeable than me in YF
– but a ball park figure would be anything between 5 to 20% of the boat's value per annum, depending on its current condition. You would also need to think about laying money aside for refits.
Boats are greedy beasts when it comes to finance. Only those who build and sell them make any real money.
But don't let that put you off! There are very few things that you can do (with your clothes on) that equal the pleasure of spending time on your own yacht - IMHO.