I went to a house that I used to live in and that I still owned. I was searching for something I needed, that was inside the house.  Just after entering the house I went to shut off the alarm, and instead saw a blank wall where I expected to see the alarm system; then I realized I’d gone in a different door and the key pad was on a nearby door. I rushed over to that door, hoping to get the alarm turned off before the siren was on very long. I saw that the system was armed, and the light blinked when I went in front of the sensor to get to the key pad, but the alarm did not go off. I also realized that there also was at least one other un-alarmed door to the house. As I wandered through the house I saw there was much less furniture, and then I remembered that I was a landlord now and someone else lived there. Although they apparently were not home, I started calling out “Hello!” and then came across two women in the bedroom. I started apologizing profusely for having come in without informing them ahead of time, and then tried to remember what I had come there for. They weren’t upset with me and we got into some conversations. I recognized a book case that was from my family when I was growing up, that I had left for them to use. No particular attachment, just recognition. In the end I couldn’t remember what I had gone there for and went outside. But my car wasn’t there, and I figured it had been stolen. I noted that at least my purse had not been in the car. I just stood there a while and then the women came out and from looking at the house numbers I realized I was on a different street, that I had gone through someone’s back yard and out to their street instead of mine. The house number I was looking for was that of my previous real-life house, that I moved out of in 2001. I was heading back to where my car was parked when I woke up. Cars, for me, generally represent my body when I am in the dream state.

For me, houses generally represent states of consciousness. Basically I had moved on from this house but a few things of mine were still there even though someone else was living in it. The house was clean and had a lot of bare surfaces. And the people were nice despite my intrusion.

In real life, I’ve had to abandon my house because of hidden water damage that resulted in microbial growth that made me extremely ill for many years before I finally got a correct diagnosis. The house itself cannot be fixed so that it will be safe for me to live in, because after the years-long exposure my system is so sensitized to the mold that is present, that I cannot even go inside that house, and also react to “any” building at this point, forcing me to live essentially outside. I recently, finally, reached a point where I’m angry at the house (as opposed to mourning it tearfully) for doing to me what it did. This will allow me to move on emotionally. I also am trying to buy some acreage to build a new, safe-from-water-damage, house, so “new house stuff” is on my mind.

If it were your dream, what might you think?

Part of my shamanic training is in dream work; we presented our dreams daily, and the question always asked was "if it were your dream, ..." That meaning that no one else can tell you what your dream means; all they can do is say what it might mean if it were their dream. I found I got many insights from asking that question, getting responses that opened up my mind to possibilities I had not thought of. That's why I ask that question.

You say: "For me, houses generally represent states of consciousness.
Going by this says, that your view/opinion was confronted.  It brought a thought, that you analytically don't understand.  In other words someone has challenged your belief.  I get the key pad, representing a computer program, while an alarm going off and the door representing your new thoughts being aloud into your thoughts or keeping it closed.   

quote: "As I wandered through the house I saw there was much less furniture, and then I remembered that I was a landlord now and someone else lived there."
You are master of little and not wanting to change, hence the less furniture.  Something inside is trying to tell you something.  Your primary beliefs from being raised up, is the woman and the book case.  You don't want to connect with a part of yourself that you ignore.  You can see this by your apologizing or belittling yourself from something you think is a mistake.  Forgetting your purpose in the dream, also shows a confliction towards your thoughts or beliefs. 
You want to move on.  Your purse is your life. Your life is secure but you don't want to do something different.

quote: "I just stood there a while and then the women came out and from looking at the house numbers I realized I was on a different street, that I had gone through someone’s back yard and out to their street instead of mine. "
Your trying to understand what to think but don't know what to do or what choice to make.

Quote: "The house number I was looking for was that of my previous real-life house, that I moved out of in 2001. "
Here at the end is showing you being stuck in the past and just going back to the way you know best, hence going back to your body/car.

I mean no disrespect at all towards you.  I know nothing about you.  This is my interpretation of what I would see.  I only tell it like i see it, which my perception is just as different as everyone else.  If any of this clicks or if none of it clicks, then please make a response.

Hope this helps
Good Journey
Thomas