NEW YORK (PIX11) — New Yorkers impatient to buy marijuana when the state’s first recreational dispensary opens its doors on Thursday have some rules they’ll need to follow.

Michael Bass, co-chair of the Cannabis Law Group at Abrams Fensterman, joined PIX11 to answer some questions Wednesday. Housing Works will start sales on Thursday at 750 Broadway in Manhattan at 4:20 p.m.

Those in line will need to be 21 or older in order to legally buy, Bass said. There will also be limits in just how much they can purchase.

“Don’t show up tomorrow with a shopping cart and think you’re going to fill it up and leave the dispensary, that’s not going to happen,” Bass said.

While buyers can share with friends, they cannot turn around and sell what they’ve bought to others, Bass said.

Bass expects lengthy lines at Housing Works, which is the only dispensary with approval to open for in-person sales. People should be patient.

“Please do not get tired of waiting in line and decide you’re just going to go over to New Jersey to buy cannabis, because if you bring it back here to New York, you’re committing a federal crime,” Bass said.

He doesn’t expect an end to illegal sales just yet, but thinks cracking down on illegal sales will be imperative for the legal program to function. For more from Bass, watch the video above.