Raccoons are wild animals - they do not create the best house guests. Some people have attempted to keep them - aside from the threat of being bitten or scratched, the major issue is they destroy everything in the house. A raccoon living in a attic of a home will cause some significant damage. I have been in countless attics so far with raccoons, and I have seen all matter of destruction.
Raccoons will tear apart ducts, sometimes all of them. I'm not certain why, maybe just for fun, possibly in search of bedding material, perhaps because they are interested in the air flow. They'll tear up insulation on pipes, tear the insulation paper off the walls, chew on cables, yes, chew on cables - I have seen raccoons do it several times - and they will trample down insulation or stuff it in areas it does not necessarily belong. Due to these problems, I urge raccoon removal once you realize you have a raccoon issue.