Here it comes....
When in engineering school in Kansas, knew a guy who previously sold airplanes... told me no matter what the gauge says there is always a little in the tank! Then there was that bigshot, hotshot, FBO at Brown field who held nearly every rating possible who landed a 150 Cessna on I405 south of San Diego because of fuel starvation! Same philosophy as the salesman. The hotshot was NEVER known to visually check the gas in a high wing plane was seen after the freeway landing to actually borrow a ladder to check another 150!
So, Major Tom. You have diagnosed the problem. The possible solution is fuel up when she says 1/4 or whatever seems reasonable. Carry on.
Glad to hear you dint have to land her in a field so small you'd have to taker apart to getter out! Har, har!