It's considered to be on par with a cane or wheelchair. 

Tenant is asking to make number of changes within the unit and in the common areas.We are ok to make the changes within the unit.Tenant wants us put on a ramp on a three step stairs so he can use the wheelchair. 

The truth will set you free...He did ask me for railings, and a wheel chair ramp.

Just like you could not charge wheelchair rent for a wheelchair. 

Woman upstairs move in a wheelchair and couple my Tenants moved out breaking the lease just in a month - they couldn’t sleep in any room of the condo.So, I have to find a problem Tenants, who otherwise have problems renting - let’s say, with eviction etc.

However, I have had people who need wheel chair accessible buildings view my units because the fourplex is a ranch whereas most apartment buildings are multi-story.  

I do know you must let them make any temporary changes they need to at their own expense for both install and removal if they are handicapped, like adding a wheelchair ramp.

sorry it was a dumb question - please delete

I am thinking of getting licensed but I a disability that would provent me from showing most properties personally (mainly those with stairs or other access barriers do to wheelchair use).My question is....would I still be able to find success?

It's no different than a wheelchair.