Here’s my $0.02.
I penned a long response outlining the many pot holes you need to avoid when transferring common property to a lot owner or worse still, selling the common property.
On reflection I have a far simpler response: drop the matter. Do not proceed. Keep as far away from it as you can. As you wrote: “The supplier has plenty of references in private houses but none in stratas”.
Do you know exactly the model chair lift under consideration? Will parts be available in future years? Will others be inconvenienced by the noise? Will the OC decide on the terms of a service agreement with the supplier or will it leave it to the lot owner?
Do you really want to be the guinea pig if something goes pear shaped? Are you or others in your OC confident, really confident that the skills and outcomes in a private house are transferable to a strata? Say you’re all in favour. Say the local council approves it but in say, 5 years bans it for any reason. The council orders the OC to remove it. Do you think the lot owner would accept the OC’s dictate to cover the cost of removal and restore the area to its pre-chair lift condition, without a fight?
The historic record will show the OC knew the supplier has no provable record in stratas, yet the OC chose to go ahead anyway.
In my humble opinion, that is not a winning hand.