We arrived at the group entrance gate in good time (10.15am) for our 10.30am slot.  Buckingham Palace operate timed entry slots.  There's no "waiting area", so it is a case of standing on the street and clogging it up (fortunately, it's quite a wide street, but it wouldn't be very pleasant at peak times) and the road alongside is not the quietest.

We were called in quite promptly at 10.30am by a cheery member of staff (who are all uniformed) and ushered to benches to get our visitor badges and be told what would happen next (which amounted to walking up a path and into the building to their airport style security).

Buckingham Palace do not allow buggies, and it certainly isn't built for them.  Therefore, if you have brought one, you must "check it in" to their "cloakroom" (you don't have to walk back to collect it, the transport it to the rear exit of the building, next to the coffee shop)

We were on a self-guided tour and the hand-held "audio guide" was included in the entry price.  There are two options - adult and child.  The adult one was quite informative (and kind of reminicent of a BBC comentary), the child one went into less detail (to be expected?) but was more lighthearted.

The tour takes in a view of the quadrangle and the state rooms.  It's frequented, as you can imagine, by fans of the royal family (whose knowledge rivals the guides in some cases - and thank you to that person who educated us in what an ermine is) and foreign tourists.  At times, these two groups are so enthusiastic, it is hard for the smaller children to get a good view of the exhibits through the three-deep crowd of adults. (Particularly in the Throne room where clips of the Queen's coronation were played and there were displays of official photographs from the day) and in the room where the clothes worn by the Queen and other members of the Royal family and party
for the coronation)

The tour is one-way (you cannot normally double-back on yourself). Since our group contained children of different ages and stages meant the group soon split up. Indeed for some sections, our family was separated.

At the end of the tour, just before leaving the building, we collected our baggage (which had been wheeled round from the entrance).
We opted not to go to the coffee shop (probably just as well, if prices in the gift shop are anything to go by - a biro was £5.99 and a single Christmas decoration £14.99)

Finally, we ate our lunch sitting on a bench bordering the garden. (On a really busy day, bench space would run out)

The visit ended with a trip to the toilets (the poshest portaloos I have ever seen) and a walk down one edge of the garden. There you are unceremoniously ejected out of a door in the wall, into a street somewhere at the back of the palace. There is no clue as to where you are and no one has thought to put a sign saying "this way to the front" (or something similarly helpful). We had planned a leisurely walk onwards to the London Transport Museum; a journey that turned out to be rather more aerobic than anticipated.

Overall. .. interesting, not least because it is where the queen lives but not worth a repeat visit unless you are an avid Royal fan or History buff.
Staff are helpful, friendly and numerous.
Toilets are plentiful and immaculate.
There is no parking and it is inside the London Congestion Zone.

Buckingham Palace is open to the public in August and September (although, there is a special Winter opening at selected dates between December and February). Check their website for exact opening dates.  Normal entrance prices are  from £19.75 for an adult and £11.25 for under 17s, under 5s are free.  Education rates work out at £5/person but with some free adult places, depending on numbers and limited slots are available and must be booked and paid for in advance. They also do guided tours and visits to the Royal Mews.