
Prepare first

Do not contact people without doing your own preparation. Do your literature review, prepare questions, write the proposal for your story in advance. It is not a very new concept.
It is basic research ethics.
No surprises please.
Once the person confirms their availability, send the information listed above in advance. Do not say things like: “oh but I do not have exact questions”. Disability includes neuroatypical folks. And most of us would like to know what to expect.
Have alternate modes of communication

Again, some prefer non-verbal, while some others prefer verbal modes of communication. It sometimes changes too.
Disabled folks shouldn’t tell you to accommodate on a piece you are writing on accommodation.
Give us time.
In continuation with “no surprises”, if you are planning on interviewing, give them AT LEAST a week.
If they have more spoons, they may be able to do it in few days but account for a week. They have to move things around, to make time and energy for you. They often operate on Crip time. So account for that.
No last minute commissions

This is especially true for commissions for events already marked in calendar. Commission them in advance. Do not expect overnight nuanced pieces. Some of them rarely do sponteneous phonecalls, let alone publish a whole op-ed.
Stipend

Offer a stipend for their time if it is not against the ethics of the research you are conducting. Most disabled folks are underemployed or unemployed. If they are sharing their lived experience that you are going to use for your career development, you should pay them for their time.
update
Once the article gets published, update those you interviewed.
