Based on the information you provide, you should be somewhere between the 3 & 4 bedroom prices but there are many other factors to consider, including age, lot size, landscaping, interior & exterior finishing & amenities.

Let me also add this info... In the area where we are putting the home for sale, 4 bedroom house of similar sq footage are listing for about 550k-600k. Our home is about the same sq footage, but with 3 bedroom, but with the large master suite that is larger than the comparable homes with 4, 3 bedroom homes. Would we be justified in listing our home in 525k-550k range as compared to 460-500k that 3 bedroom homes are listed?

A suite is several rooms (think hotel room vs hotel suite). While a Master bedroom with private bath could qualify, the office & dual walk-in closets certainly make yours a "Suite". The value isn't added by using a particular phrase, it is added by the square footage , utility and finishing of the space. The terminology just paints a better picture in trying to interrest a potential buyer to see the home.

Yes, I would call it a master suite. It would add value above similar homes that don't have the square footage. Beyond the space, it's the floor plan, finishes and how the space is showcased!