Your idea makes so much sense, and it's something many families consider or actually do. I do not know of any financial aid to help you buy a house. Some
brokers (and housing agencies) offer low-interest home loans for people with disabilities. (Legitimate loans.) Your parents should talk to banks and mortgage agencies in their area about this possibility. It's also a good idea to check with their local governmental (city or county) housing agency about housing programs for people with disabilities. Government assistance is almost always for renting not buying, and income-based. To qualify, you or your parents would need to meet low-income standards. (Which you may.) You can also check with local disability organizations in your parents' area for housing programs. This takes effort, but is worthwhile, as many programs are offered on the local level. Good luck with your efforts.