@JustBen. Please don’t pick the first EV you test drive. Especially if you have to compromise on your normal use cases.
Go test drive some other EVs in a similar price bracket. If you want a very premium Audi with a big boot, there are some decent E-Tron 55s out there for ~£20k - £22k and 40,000 miles or less. Or if you prefer a less premium and more economical yet practical EV, an Enyaq 80 AWD is a great option.
Look at some of the Korean stuff as well as a Model Y for some very good practical EVs. Far more practical and drive just as well or better than a Tesla Model 3 saloon.
I’m not knocking the Model 3, just that if you are already considering roof bars, then clearly a saloon shape is a major compromise for your needs. There are more than enough used EV options out there that won’t require such a compromise.
Edit: Sorry if I am making assumptions on your budget.