Vince,
I am an advocate of getting the chair early. It is what I did and what I recommend everyone do.
The benefits are many, including:
1. You still have the ability to adjust the chair to fit you rather than relying on someone else.
2. You get to know how to use the chair and navigate it around obstacles while it is still practical to get out of the chair and examine the situation.
3. My primary chair required quite a few trips back for repair. It was easier to arrange for this when I could get by without it for a few days.
4. You will need to figure out how to transport the chair (public transport, ADA transport, your own van). This will give you time to do that. It took me several months to figure it all out and buy a van.
5. Using the wheelchair conserves your energy. I can't emphasize the impact of this enough. Just sitting in my primary wheelchair allows me to feel better the next day. It has wonderful trunk supports. I don't have to use them, but I am fresher the next day if I do use them.
As a simple example, I needed to get a particular medical test where they wanted me to sit on a table completely unsupported and look up for about 15 minutes at a series of flashing lights. There is just no way that I could have done that. But, I was in my wheelchair. We moved the table and I rolled my wheelchair there. I hit the seat elevate and tilted the seat back a bit so that I would not have to look up. That made it a breeze to do the test.
Even though I can still walk a bit, I discovered that I can't be without a wheelchair. Since mine was in the shop a few times (sometimes for up to 2 weeks), I decided to buy a used chair as a backup. I then got a 4x4 wheelchair and now have 3 wheelchairs.
Because I have a wheelchair, I was able to get out of the house today and go for a "walk". There is no way I could do that on my legs.
I encourage you to start the process now. It did take me 4 months to get my primary wheelchair.
Steve