Mojave's answer is correct. In case you are interested, here is some additional information about the expression and its usage: The expression "in a sense" can have a couple of different of uses. It can mean "one way of looking at something" in terms of perspective, or it can mean "basically/essentially/practically." The man in the story didn't need to go to the exact house because he had essentially been there before. Using "essentially" in this way implies that he has not actually been to that exact house, but instead it implies that he has been to a lot of similar houses; and therefore, he might as well have been to this one before. The expression can also be used to compare two different perspectives for the same situation. Here is an example, as well as some other expressions that can be used in the same way: 1) In one sense, he did well because answered nearly all of the test questions correctly, but in another sense he did not do well because he went over the time limit for the exam and lost some points. 2) On one hand (or "on the one hand"), he did well because answered nearly all of the test questions correctly, but on the other hand he did not do well because he went over the time limit for the exam and lost some points. 3) In one perspective (or "from one perspective"), he did well because answered nearly all of the test questions correctly, but in another perspective he did not do well because he went over the time limit for the exam and lost some points.

He has never actually been to this house in this city. But the house is similar to houses he has actually been to in other cities. So even though he has not been to this house, he knows what to expect, he knows where it is, etc. Because it is similar to the other houses. That is what is meant by "in a sense".