@SilverArrows @actuallyautistic
It's important to remember that everyone, no matter who, is apprehensive and often fearful when it comes time to leave home. And I really do mean, everyone. Also, that no-one knows how to do things like opening their first bank account or renting property. This is why parents generally have to go with us and help us through these things for the first time. If we're lucky, that is. Otherwise, it's generally just blunder along and hope that you're helped by a friendly member of staff.
The autistic anxiety that goes along with these things is, though, unique to us. A lot of it comes from simply not having the relevant information. Of not being able to prepare ourselves with doing the research and thinking through the various options ahead of time. There may also be anxiety that is more indicative that you're trying to move too far outside of your comfort zones, too quickly. This, I think, should be listened to. For example, you may not want to leave London, because you're comfortable there and know you have a far greater chance of coping there, than anywhere else. It's always worth remembering that our anxieties and fears may only look irrational from the outside and to someone who doesn't understand us. They're often based on perfectly logical reasoning, from our point of view.
If you have no luck finding help from the various organisations, or mentoring programs. Perhaps you could just pose your questions to the autistic community here. Most of us are older, have gone through this and may well be able to give you the information you seek.