re: How do you add fuel?
Similar experience some 30+ years ago - probably 1990 or 1991.
During the economic crisis in the early 1990s I'd been summoned for a meeting with the European Corporate Computer Services Group HoD to 'discuss' the budget for the Open Systems strategy programme I was responible for. HQ offices were in Cheshire and I was based on Teesside.
Company concerned (global/empire-wide manufacturing Chemicals, Pharmaceuticals etc) was more concerned with employee safety with so many employees and contractors driving between the Northeast and Cheshire/Manchester/Merseyside each day than environmental impact so had arranged a regular commuter flight (Jetstream 31 typically) several times each day between Manchester and Teesside airports.
So, I booked the standard package of day return flights and hire car from Manchester Airtport General Aviation terminal (then roughly where T3 is today). Arriving off the plane at lunch time I was greeted by the car rental guy handing out keys to the various travellers with something along the lines of "who's the luckly one today!" and instead of pointing me to the typical Ford Orion or Vauxhall Cavilier he showed me over to a Rover 800 Sterling - at that time must have been worth roughly the value of my mortgage!
Off I go for my meeting with Eddie in Wilmslow, feeling very guilty about the potentual cost of the car hire (although in retrospect I expect that it was charged at the booked level rate), get chewed out as expected about programme time and budget overrun and make my way back to the airport, stopping off at a filling station around a mile away (company policy was always to top up cars before return, even where the mileage was low - in this case around 15 miles). Pulling up to the pump I started looking for the filler release: there must have been 30+ small buttons on the central console (no touchscreens in those days, nor Google!). Could I find the relevant one? Nothing I could see looked at like the right one, and I didn't fancy pressing any at random on a car like that, nor was there a manual in the car. Even got out to see if the filler flap was just press to open. Nothing!
By this time there's a queue starting to build behind me and horns are starting to be pressed. Well reader, what could I do? Yes, I got back in the car drove off and returned it without topping off.
Fortunately never got a car as fancy as that one again!
Even more fortunately I never heard any complaints about either the cost of the car or the need for it to be refueled by the hire company.