Oh no, it's not a misconception. Animal breeding and management is the correct place to start, but you also have to build a milk house that will be certified by your local state agency. That is VERY expensive. Before you start aquireing a herd, look into the costs of a milk house. Outfitting the building according to code, buying the equipment, setting up the plumbing and power are huge expenses.
There are lots of variables. First prices vary depending on your location. Also, do you have the land for 50 cows to graze? Do you have livestock barns? Do you have a milk house? How many cows do you want to milk at a time, that will determine how big your milking parlor will be. Where do you plan on getting your heifers? Are you going to have registered Holsteins? And most importantly, do you have a market for your milk?
I think that most new farmers fail to research well and incorporate every cost before starting. Deciding the type of cattle to be bred and conducting a preliminary investigation of the soil type and vegetation in the area could be helpful. It is a highly profitable market requiring an equally sizeable investment.
Dairy farming in Suffolk County!!! Hmmmmm.... I'm originally from Suffolk County, I don't think there's been a dairy farm there since the 60's. What would your market be? 1 -2 acres is pretty small for 50 cows, and hay is probably REALLY expensive on Long Island, but check it out with the cooperative extension.
Good luck!!!! Keep us posted on how it's going!!!