I think that you might be trying to rush through too quickly. I started over with the last update, and I was probably on day 40 or 50 before I added a second room, and day 70+ before I added a third. If you take it slower, its easier to handle.Laura has no impact on the number of guest that you can receive. But to answer your question; Yes. As so as Amanda becomes available I get her. When I get Amanda I keep the guest level set to 2 until all everything and everyone is at Lvl 3. This helps to prevent unsatisfied guests.
The number of guests is based on either the number of rooms that are available or the level of the Lobby waiting room. On day 17 I added 2nd bedroom and upgraded Lobby waiting room to Lvl 2. Never received 2 quests at the same time. On day 62 the Manor was fully upgraded to Lvl 3 and Julia has 1599 skill in the Lobby. That is when the problem starts.
I think the problem is due to the fact we only have 9 quest right now. With each guest receiving a turn to ck in. It's a cycle. When all guest have had a turn you get no guest for up to 3 turns on the same day and you may go 2 days with no new guest. It may be due to the fact the game does not keep count of the guest in the manor in relation to your capacity at ck in time.
Anyway, perhaps it will be different by the time we have all 5 rooms and all the guest that the game is going to have has been added.
If you are correct about not receiving a penalty for refusal of a guest due to being full, then there is no real problem. Thanks for you response.