As a previous owner of an Audi BEV, I already have a charging station in my garage, which I'll be using for my Aviator PHEV whenever it arrives. If I didn't have the charging station already, this is the way I'd look at it: First, even though the PHEV doesn't have a huge battery, I'd want to use 240V charging, not 120, to reduce the charging time. If this meant that I had to add a 240 circuit, I'd for sure make it a 60 amp circuit, just to future-proof the installation for when I (inevitably) own an BEV. Buying a charging station would be optional until I needed it for a BEV, but I'd probably do it from day one anyway, so that I had a clean, hardwired installation rather than an outlet for the Aviator charging cord that'd I probably need to change once I had a BEV.
This is what I'd do, but other options are perfectly reasonable.