You're going to have to have someone come and take a look, there's no way of estimating without seeing it as there are too many variables that aren't known. (Number of trees, proximity to other structures or powerlines, size of trees, elevation of lot etc)
Good luck, Lewes is a great little town, I know it well.
Did you already buy the lot? There are so many lots available that do not need clearing. If it must be cleared consider harvesting if the trees are mature hardwood. You can offset the cost of the rest of the clearing by offering the hardwood to a user.