The non-overdated 1806 Quarter is the collector's best choice for a representative example of the Draped Bust Type. The 1796 and 1804 Quarters are rare and expensive, the 1807 is seldom fully struck, the 1806/5 is s trifle bit more scarce, and the 1805 is hard to find in high grade. This leaves the 1806, which is semi-scarce (as are all Draped Bust Quarters), but it is the most plentiful of all the Draped Bust Quarters and it is the most available in Mint State (in full disclosure, the 1807 comes close).
High grade examples are not rare, but they are expensive because collector demand for type coins of this period is so high. The PCGS CoinFacts Condition Census of the top ten examples starts at MS64 and ends at the MS65 level, where a couple of Gems reside.
Non-overdated 1806 Quarters include nine separate die varieties.
"Colonel" E.H.R. Green - Green Estate - Partnership of Eric P. Newman & B.G. Johnson (St. Louis Stamp & Coin Co.) - Eric P. Newman, who paid $15.00 - Eric P. Newman Numismatic Education Society - Heritage 11/2013:33332, $94,000
B-9. Louis Eliasberg, Sr. - Bowers & Merena 4/1997:1363, $35,200 - American Numismatic Rarities 12/2005:543, $71,300 - Joseph C. Thomas collection - Heritage 4/2009:2317, $74,750