Hi, I'm in MBSJ area, seller did two extensions, first one long time ago was ground floor all the way to back (got permit), but more recently did a 5 foot extension in front without permit.

Now as the new buyer I wish to extend the first floor all the way to the back as well, and add 5 foot extension in front for first floor. I believe need to pay a saman at MBSJ and submit plans? Is there any benefit or potential problem for me to ask seller to self report and pay saman first?