I just use the sale tables from the various packs we have. To get more sims to come to the lot, a Marketplace (Eco Lifestyle) lot type might work. The downside of that is your sim has to live in the neighborhood to change the Community Space to the Marketplace setting.
Also if you have Home Chef Hustle, your sims can cook waffles and pizza while at the sales table. The sales table works like the other ones from the other packs except there's room for the small appliances that came with the pack.
You may have to start another event once one ends to make any real money. If I remember correctly, you may have to interact with the customers some as well. There is a sure sale option (or something along those lines) that makes a sim buy immediately but it has a cooling off period. You can't spam it.
Edit: I just want to clarify, you can cheat the Community Space type by shift-clicking on the community board. That helps to bypass the voting and possible losing the vote, unless you have NPC votes disabled in the game settings.
