If you are looking around online and have your own realtor, find a home you want to see, or they notify of one you may like, when it comes to being shown - it may say "No showings of the property until the upcoming open house!"
There are a few reasons for this - but I will give you the Three Top Reasons why a home will not be allowed to be shown until the open house.
1 - The agents want the listing to populate the internet on sites like Zillow - Trulia and Redfin in order to get them leads because they pay those services in some way.
2 - The agents want time to do mailings to the local neighborhood seeking other sellers who want to sell also in order to potentially play each listing against each other.
3 - The agents want time to advertise the listing to their buyers and other agents in their networking groups in order to bring an offer to the seller before any showings.
Reason 1 - the short view
In the long run - any real estate listing can be used for leads. If there is an agent paying sites like zillow, trulia and the other real estate syndication sites - the leads which are generated could be plentiful.
If they put the home on the market and right away get an offer, that maybe the one the seller wants to go with, thereby cutting into their advertising power. - so hence the run time before showings.
Reason 2 - neighborhood competition
When we speak with sellers, the last thing we want is to have another listing which will be in competition with our seller. We inform them during the contracts about the form that speaks about other people in the neighborhood possibly wanting us to represent them in the sale of their homes too. I explain I don't like the "unfair competition" aspect and I will always recuse myself if they don't want me taking any listings which will conflict with theirs.
I'm in this real estate business for the long haul - no need ruffling any feathers with those who trusted my services first!
Reason 3 - an inside offer
You already know that in order to ensure a seller is getting the best possible offer, their real estate listing has to be advertised everywhere. The home for sale should hit all the local Multiple Listing Services, the internet home syndication websites and the local agent's email.
Every agent will tell you that any offer received before these steps take place cannot be guaranteed to be the best - so why would a seller jump on it?
The same applies to a real estate agent doorknocking or mailing you that they have a buyer for your home. Maybe they do, if that is the case, and if you want to sell, hire your own realtor then say to the other agent with the buyer, bring them on and speak with my agent!
Open Houses and your protection
You can go to all the open houses you want. Just tell those agents/people hosting the open house you have your own realtor. You have the agent you want to work with and they will(should) leave you alone.
At least, most agents will leave you alone, if they don't, let your agent know who they were and your agent will read them the riot act. Or they should.
We have had our clients, those who were most verbal about already having a real estate agent while visiting an open house, still pressured to use the agent hosting the open house. After they spoke about how unethical that was on their own social media channels...
Paris stepped into this agent in person, on the phone and all over social media, he will not make that same mistake again.
Also, we go with our real estate buyers to visit open houses all of the time. They ask, and I deliver. I want them to feel comfortable when visiting open houses, so me being there is a great thing.
Reminder - when visiting new homes without your Realtor, don't sign anything!