@Claire1557 my houses have LOTS of flaws. One has no internal access between floors (yes, you saw that right), all have tiny parking spaces, one has a train passing every few minutes right behind it. I charge an insane amount of money and if I get unhappy guests, they are usually are not happy about other things.
I do not necessarily agree that you should lead with a negative with a title. I also do not agree that your access is that bad. By Chicago standards by having a parking space you are lightyears ahead of the next competitor. Someone from a big busy city will not think twice about this. I back into a really busy street down a very narrow alley with my own car. I literally have six inches on each side of my car as I back out for half a block and then straight onto one of the busiest Chicago streets that connects a highway with an expressway.
First, capture your future guests with an amazing listing description, draw them in with positives. Once you are past that, put the flaw in multiple places: the space (second paragraph, do not lead with it). getting around and also in things to and things a guest must acknowledge. At this point no sugarcoating.
This not so atrocious that guests would have to cancel if they did not realize this, you are fine offering IB. It is not like they will be in and out all day long. Furthermore, terrible access can mean so many things. I have been doing for many years and still perfecting my description. People continue to surprise me with how they interpret simple sentences. I to be honest first thought that you do not have a front stair or something like that or there is a ditch you have to jump over.
You have a wonderful property and you will have many happy guests, I am sure of it