Your best bet is to call them for current rates. https://www.singercastle.com/reservation/
There are plenty of hotels/motels in the area
Our guide said $750 for the first 2 people and then $75 person up to a total of 8, check in when the last tour leaves and check out before the 1st tour in the late morning.. and you get the run of the castle with a few staff to accommodate
Yes that would not be a problem
It is around a thousand for one night with catered dinner for two people.
Check the website. Prices vary depending on number of guests
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