How early should they arrive?
Early enough to make sure that everything's in good condition. Early enough to turn on the light in all the rooms, open the draperies, etc. They're not maids, but if something is clearly messed up, enough time to try to fix/clean it. Enough time to put out a sign-in sheet and other literature promoting your home. If they're going to do something like bake cookies, early enough to accomplish that. So, the question isn't really: How early should they arrive? Rather, the point is that they should arrive early enough so that when the open house begins, they're ready and your house is ready.
Should the open house be advertised, or are street signs enough?
Depends on your community. Generally, I'd say that the house should be promoted. That doesn't necessarily mean ads in the papers--which (at least where I live) can be very expensive and not very productive. I'm sure in other areas, ads work fine. But it should also be noted in the MLS. And lots of agents post open houses on Craigslist. Others--who are planning ahead--will do a postcard mailing to neighbors announcing the open house. Having said all that, if an agent has found that street signs are the most effective, perhaps that's enough.
How far in advance should it be advertised?
Again, it all depends. But maybe 1-7 days. Some people just open up their papers Sunday morning (or whatever day) and look at what's open. A postcard to neighbors--a couple of days, maybe. You don't want a big time lag, because then people may forget about it. Craigslist--regularly (a constant presence, that is) for a week. Again, those are just rough guidelines and customs, practices, and people's expectations may be different where you are.
The "Open House" sign doesn't show the time.
Most of them don't. In many areas, houses are open for some standard time frame--such as 1-4 pm. There's nothing wrong with putting on a time, especially if it's either beginning earlier than normal or running later than normal. But for people just driving around, or even those who've seen some of your agent's marketing, if the sign is up, it means the house is open. And after the open house, your agent takes down the signs, so there's no need to rely on the sign to say "time's up."
It sounds as if you have some concerns about the way your open houses are being handled. The best thing to do is talk to your agent and say: "For our open house, you did __________. Can you explain why you did _____ and not __________?" I expect your agent may have a logical explanation.
Hope that helps.
I was in your area not long ago, beautiful country, Doylestown is really quaint.
Most signs put out on the day of the open house are directional, but also flag passer-bys. These are there during the Open House so times are not needed for those signs. There are "riders" for the top of the main sign, generally on the front yard that can placed days in advanced and indicate day and times of the Open House.
Your agent should already review in details and expectations of your property for the Open House as well as showings. The property needs to appeal to the most people to envision themselves living there. Too much clutter and personal items can interfere with people seeing the actual house.
Staging can be your best advantage, sometimes just a few changes, like a clean-up, and less furniture can have a better showing.
1 to 2 days should be plenty to advertise, when someone may start planning an open house tour....
It shouldn't take too much time for your agent to set up for the open house, most of the time will be the directional signs before arrival.
Long & Foster Real Estate
I usually put it into the system a week before, however I think most people only search the day they are going out.
Keep in mind that less than 1% of home buyers find there house from an open house. Open Houses are good tools for a lot of reasons, but they are not critical for selling your home.