Just to answer one of your questions. The NADA pricing doesn't take into account the real market value of the eggs. The prices you are seeing are what the market bears for the eggs. Because they are very durable and in some respects short supply, an egg's asking price reflects that reality. That's not to say you can't find lower priced eggs, but they are fewer or farther between.
And not to be snide, but the best trailer for the money is the trailer you pick based on your needs, wants and wishes. If you are a fixit up sort of soul, an egg needing some rehab will let you make it into your own vision. If you would rather not rehab, a new or newer egg would be better.
The buyers checklist is an excellent tool for evaulating the eggs you find and an excellent tool for helping to determine exactly what your wishes are in reference to how you prefer to camp.