I am on power wheelchair #3 and have a section of my website all about the process of ordering a wheelchair including choosing a brand and the necessary features and the paperwork process. ALS Patient Care From Both Sides: Wheelchairs
I can't help with specifics, but can tell you how it went with us so far.
My PALS just went to the wheelchair clinic last week. They discussed his needs and my needs as a CALS. He has extreme FTD so his PWC will be attendant controlled. We discussed manual vs power. After I saw all the ways the PWC could help me and his other caregivers care for him, it was a no-brainer to go for the PWC. A rep from Permobil came to our house the next day to see the layout and measure my husband. The VA does all of the paperwork to order the chair, the company makes the chair VERY QUICKLY, and ships it here in 2 days. They will then deliver it. The rep we saw said to call him and he will come and program special settings to help us with what we need. It seems the longest part will be the paperwork at the VA, but they said to call if we haven't heard from then in 3 weeks. We ended up with a Permobil M3.
the va, after measuring you, and knowing home circumstances will choose your chair. As things change for you, the will add and delete attachments....tablet or phone holder, trilogy mount, attendant control, roho cushion, etc
the va ordered a permobil for me and the permobil rep came to the house and reviewed all options available. some options I declined since they seemed frilly. appeared the va would approve all options which I believed would be needed. let's talk if you would like info on the permobil rep. she might be able to provide insight on your fitting at the va,/frank