Walkups generally open around 11.30 am to midday. Most close around 9-ish in the evening depending on how much traffic there is, but those that have late night shifts (e.g. 52 Greek Street, 34 Romilly sometimes, etc.) generally operate a £10 extra late night tax to deter, and compensate the girls for, the extra levels of drunkenness, bullshit and unpleasantness that is more of a possibility at those hours, as well as the extra stamina that's required, I guess. The extra ten sovs is pretty standard in Soho and I reckon that's fair enough but it might be put on menus or clarified if it isn't. I generally tend not to visit much after 5pm at the latest as the levels of service in many (not all) instances decline after that hour with tiredness (made worse by the after-work punters). Lunchtime hours can be a little rushed, so I therefore aim for either the earlybird 11.30 session or one around 2.30-4-ish when there are likely to be less rings of the bell. Not always possible for me, of course, but those are my ideal times.
With regard to Kim's behaviour at 8GS, this wouldn't be regarded as acceptable by the mama-sans at that venue. As noted above, let the maids know if you don't stay and think the pricing is out of order.
