Maryland is one of the easier states to find colonial money from. Consequently, they tend to be affordable. What can affect the value of a colonial note is the state it came from, the printer, or even the signatures. There are some colonials that have signatures of some of the founding fathers. For example, some colonial New Jersey notes bear the signature of John Hart (1711–1789), who signed the Declaration Of Independence. The note featured below has none of these features but I find it an attractive colonial with an interesting denomination. Since colonials don't have the beautiful elaborate vignettes of broken bank notes their values tend to remain stable, increasing ever so slightly over time.
$4 Colony Of Maryland
Image Contribution: Handini
Currency was still in the process of gaining acceptance by the masses so they made these notes backed by gold or silver and assigned the penalty of death to those who counterfeited currency. This was generally executed by hanging the counterfeiter.
Here is a post with more information on colonial Maryland notes on someone else's blog: http://coinsblog.blogspot.com/2011/01/old-maryland-notes-new-owner.html