Get a accessible handicap home for my son

Hi, my name is Amy. My son Tyler was diagnosed with friedreich's ataxia a few years ago. This is a genetic disease with no cure. Affects mobility and coordination. He has tried to live a normal life. As much as this disease allows. But unfortunately, he is getting where he is wheelchair dependent. We live in a townhouse with stairs and it’s getting very hard for him to hold the rail and come down. I’m scared of him falling. I’ve been searching for an accessible home for months with no avail. Covid left the housing market and rental market in shambles. I’m trying to raise money to buy a double wide and have it modified to be accessible. I would appreciate any support. Thank you in advance for reading this.