Cool, so you went through the same four background checks I had to go through along with a search in each entrance getting on to the grounds then another entering the WH even though I had a badge for that week. Right?
This was many years ago during one of a several times I was in D.C. as a lobbyist along with other group members from AFT and OSEA. If I remember correctly, OSEA's (Oregon School Employees Association) Government Relations Specialist did a lot of request work for our group which was also coordinated with OSEA's affiliate union AFT (American Federation of Teachers). AFT’s headquarters are in D.C. I honestly do not remember there being four security clearances, but it is possible that there were.
Besides the Whitehouse tour, another union member and I had lunch in the Senate dining room with House Rep, Kirk Schrader. This was also arranged by OSEA's Government Relations Specialist. An interesting side note: the chairs in the Senate dining room are the exact same style Chippendale ladder back chairs as I have in my dining room only with different upholstery. We three walked from Schrader's office through an underground tunnel which runs between The House and The Senate to get to the dining room.
As for searches. As I mentioned it seemed like every building I visited, both government and otherwise had an elaborate process to get in. In some cases, our names were on a list which was provided in advance of the visit. In a couple of instances, our group was escorted by security to the exact location of the floor or offices we went to. This rigmarole was both disarming and annoying.