I cannot speak specifically for Arab street since some shops may stay open longer than others, but usually shops will close between 9pm and 10pm esepcially in malls. Street shops often close a bit earlier, some as early as 8pm but since this is a tourist spot with a lot of people around at night many shops may remain open till a lot later. This is a very busy area at night with lots of bars and restaurants in the adjacent Haji Lane and North Bridge road so expect lots of open eating places at night too.

They open around 10am and stay open till late depends on the day of the week also

I don't think it will be an issue. There are lots of people with tattoo's these days. I have them on my wrist and no comments were made. If you do feel uncomfortable maybe carry a long sleeve top in your bag.

Hi, Bugis Street MRT Station is just around 500 meters away from Bugis Street. That should be the closest.

Yes the Parkroyal on Beach Rd and the serviced apartments if your staying seven days or more

Конечно, это же араб стрит;) можно даже устроиться на мягких подушках прямо на улице, а можно и в помещении покурить

I think you can park in all the surrounding streets. We staid on Sultan street and there was parking available.