Raccoons are a serious problem, they come on your property looking for food and if they find it they may decide to stay and make a den. The key to keeping them from staying is removing the things they want which is access to food and water, preferably easy access. If you remove these things then animals on your property may not stay. They may leave to find somewhere else to live. However, during the baby season, a raccoon female does not need a reason to break into your attic so if this has happened then you will need to call a professional. Professional wildlife technicians are highly trained and experienced at what they do, they are insured against injury and can get the animal ut in three to ten days. A contractor may not know what to do with the situation and may try to trap it in the attic which can be very dangerous. If there are babies they need to be found and are often buried in insulation. A proper wildlife tech will have an infrared camera to find them. Doing it yourself is possible, you would need to get all the tools, a raccoon one-way door and galvanized rubber-coated galvanized steel mesh to attach the door to the entryway. Get a drill that can drill bolts and very wide washers or you will be fiddling with the steel mesh for hours trying to get it to stay on. This is also very dangerous, if you fall there will be no medical insurance or life insurance provided by a company that could keep you safe while up on the roof.
If you have raccoons on your property and you are worried they may want to stay make sure to remove all food and water access. A birdbath and a leaky hose will keep them on the property. Dog food, food left outside and even a dirty barbeque will attract raccoons. If you take precautions and remove detritus they can hide in, remove fruit and berry trees and keep your garbage locked in a garage or shed then most animals will wander around for a while and then leave. If this does not work then call a professional to do the removal. Risking your safety or getting someone who has not been properly trained and who may not have at-heights training could be in danger of doing the work.