You can change or add names to real property titles at anytime. However, it is IMPORTANT to note that if you have a mortgage, you will be in breach of said mortgage agreement if the title name is changed. For example if the house is under person A and A has a loan with Bank, and if A transfers or adds B to the title, the Bank will consider it a breach. Of course, the Bank may not find out that A transferred title until the Bank actually does a title search.