As toowonderful says, the prices of Manhattan hotels vary widely depending on the day and what’s going on. What is cheap one time can be literally hundreds more the next time and vice versa.
But you can always find a good deal if you use a decent search engine and/or call around. By “good deal” I mean $110-$130/night for 2-4 per room. This is excluding parking your car, if you have one.
Also while it’s nice to be within walking distance, you don’t need to be; being within walking distance of a subway is what’s really important. Since Pearl is a quick walk from 34th/Penn station, you can really get there from most places. Take a look at a subway map for help with this: http://web.mta.info/nyct/maps/subwaymap.pdf This will help you with other audition sites as well.