There will definitely be problems with taxes and researches about your income. You might get into some trouble with the authorities if you don't fix this issue with legislation and papers. You never know when they can track you, so it's better to be prepared for any situation which might happen. If you don't have experience in this field, it's better to ask for a professional service, with lawyers and all the stuff, like egaloutsourcingservices. for example. They have some really good professional which can help you with all the documentation.