HPW - if you drive along the Choppington Road - A196, from Jonathan Scott's there is a Vauxhall garage - Davidson's of Morpeth - Coopies Estate, just before Stobhill where I got my Meriva. They have a 'Mobility' specialist - Alison Owen and they have (according to their web site) New Zafira Tourer & used Zafira & Zafira Tourer. There Motability section normally deals with customers purchasing vehicles via the Motabilty Scheme (DLA/PIP - WPMS (War Pensions Motability Scheme) but naturally they will sell to anyone with the money.
I have looked at many different cars (over the last 10 years) with a view to disability aids fitting in. It's ages since I looked at the spec on the Zafira as it was too big for me, the wife and 1 mobility scooter. What I did find with the Meriva (compared to loads of other makes & models) is that the back seats do not have to be taken out to fit in a complete mobility scooter. I am assuming the Zafira seats will be the same as the Meriva. The back seats of the Meriva fold down flat so there is no 3-4" step, between the book/back floor and the seats. In most other cars the seats had to be removed to get a flat surface that is almost essential to keep the scooter stable. I am assuming that the Zafira spec is very similar to the Meriva spec. I have never been a car 'geek', for me a car is to get me from A to B so I can do things. The son-in-law and two grandsons dismantle cars, soup them up; show cars etc. etc. I used to wind them up by saying I want a blue one next! Anyway I have had no problem with any of the 3 1600c & 1400cc automatic Merivas I have had. Excelleration via pedals or hand controls I have found excellent - not a geek but still like to move easily and quickly away from stationery positions at lights and Moor House Farm roundabout!
Before the Meriva we used to have to dismantle the mobility scooter to get it into the boot of the car we had then. What Davidsons would probably advise yo to do is talk to Bewick Mobility - Blaydon Industrial Park, Chain Bridge Rd, Blaydon-on-Tyne NE21 5AB - Phone: 0191 414 0240 about what adaptions can be made. And you will no doubt be aware the adaptions these days are endless, but also costly, and all firms are after your money. I have dealt with Bewick Mobility for 6 years and I can't fault them. Prior to Bewick many local garages gave me advice and suggestions that really were based on sales and not improving mobility experience and I always had to do more later on.