Character Modelling Ongoing

So far I'm sculpting the character's clothes and putting everything together. Getting my character model to this point is more than I expected because luckily Jack found a free model on the internet which almost looks the same as my character. But that doesn't mean I'll be using this free model as it is. I need to modify and re-sculpt it to make it looks like my character. I only use the head of this free model which has already rigged with some facial expressions. Currently I still get other parts done and leave the head to Jack because I don't know how modify it. Also I downloaded a free "Hand" model which looks very good, and this save me a lot of time.  

1 problem that I'm having is when I convert the Subdivision Polygon to Polygon and then delete the subdivision polygon but there's a polygon I cannot delete. I find this very annoying so I just Hide it.. not sure if it's right thing to do!