If you like to have 陪月 days & nights, I recommend you to have 1 day time 陪月 & 1 night time 陪月. Reason:
1) 陪月 is human. She gets tired too. 24-hour 陪月 still needs to sleep...usually a few hours a day. You can imagine her working 26 days straight with no rest. Performance may not be good.
2) I hired 1 day time (around $13K) and 1 night time (around $15K). So total is around the same as one 24-hour. But the 陪月 will be in normal condition to work instead of very tired. Of course, price might have gone up now but should be around this $$.