Attending w/o a Broker

I had a question about attending an open house without a broker (buyer's). Does it create any problem later regarding bringing in my own broker into the process if I want to make an offer on the property in so far as their 'cut' of the commission? Also, if a property is by appointment only, is there any problem with calling and making an appointment w/o a (buyer's) broker. Will I be deemed a less serious buyer or not worth broker's time? Not talking about a prestige properties, but UWS $1.8m-$2.5m type properties. Wife and I want to start poking around on our own to get a sense of how serious we may be about an upgrade, but if we see something we really like, don't want to limit our options. Thanks