You can't even sell milk locally without an approved facility, depending on local laws and restrictions by the state it may include how big the structure must be, type of containers used, how many sinks, drains, material the floor is made of, how thick the concrete slab must be etc. Then of course you have to factor local planning and zoning and what requirements they have for various inspections (which cost money), waiting for approval to continue building and so on.
In one state, an 8x8 foot structure with power running to it required 3 or 4 inspections because it was on a concrete slab on private property. In that same state, same property a structure that was 10ft by 30ft required no permit because it wasn't on a concrete foundation and deemed 'portable'. In another state entirely an 8x12ft structure required no permits at all.
As others suggested, for basic ejuice (not including what type of required facility) requires submittal to the fda for approval at a rather hefty sum and a different application (and fee) has to be paid for each flavor and each strength of juice. So cherry juice at 3mg, 6mg and 12mg requires three submissions and three fees. Labels also have to be submitted for approval. Grimm Green was talking about hurrying up and changing his labels before the cutoff date last year because any change in lettering/design would require a new submission.