With the imminent opening of the latest Gus’s Community Market in San Francisco, brothers Dimitri and Bobby Vardakastanis have much to appreciate this year, such as a thriving company with four beloved grocery stores in the city.

Yet for the brothers, it is also a bittersweet affair — this will be the first Gus’s Community Market to open without Gus.

It’s been only a little over a year since their father, Konstantinos “Gus” Vardakastanis, was killed by a hit-and-run driver while crossing the street during an early morning trip to the San Francisco Produce Market in the Bayview.

Though the investigation into their father’s death is ongoing, the brothers are forging ahead with the latest outpost of the family-run neighborhood grocery store that bears his name. Located in Mission Bay on Fourth Street, it’s scheduled to open the last week of December.

“We both know he’s physically not here, but he’s on our side as (we) move forward on it, and I’m sure he’s proud,” says Dimitri Vardakastanis, 37.

Born and raised in San Francisco, the brothers started working in the family business when they were kids — “stocking shelves, cleaning shelves, standing on a milk crate behind the register,” says Bobby Vardakastanis, 35.

Their late father, along with his wife, Georgia, opened the family’s first market on Haight Street in 1981. That was followed by an outpost on Noriega in the Outer Sunset a few years later. In 2015, they opened their third store at the corner of Harrison and 17th streets in the Mission Creek neighborhood.

Now comes the latest project, in the shadow of the ballpark. At about 10,000 square feet, it will have a similar footprint to the Harrison Street location, along with many of the same offerings.

Shoppers can expect high quality meat and seafood departments, as well as hand-picked fresh produce — the cornerstone of the family’s markets. There is also a wide range of prepared foods, a number of which are based on their mother’s own family recipes. (In addition to looking after her grandkids, Georgia Vardakastanis is also working on a cookbook for the market.)

As the market settles in to daily operations, the brothers expect to tweak things to better fit the demands and quirks of the neighborhood. One new addition to the Fourth Street market, for example, is a ramen bar, which will eventually be added to their other locations.

“That’s the beauty of being small and nimble. We’re at a stage where we have a mold but we can still flex to what the neighborhood needs,” says Dimitri Vardakastanis.

Like the other expansions, the Mission Bay project is another a way to give their employees new opportunities for growth within the company.

“To us, that’s a dream come true when you see people growing with us and put their faith in us as a business,” says Bobby Vardakastanis. “They’re trusting their livelihood to us. We take a lot of pride in making sure we do our job correctly to protect everybody.”

The Fourth Street market isn’t the full extent of the family’s expansion plans either.

In the past three years, they’ve tripled their warehouse storage space so they have enough room to hold the bulk of products they acquire as part of their ongoing efforts to keep costs as low as possible for customers.

Come 2020, their tiny Noriega market will move up the block to a new location at 44th Avenue, allowing it to expand its footprint from the current 2,500 square feet to roughly 11,000 square feet.

“It was something that — especially after expanding our Haight Street store — our customers in the Outer Sunset were asking for,” says Dimitri Vardakastanis. “People love our Noriega store. We love our Noriega store. We just want more of it.”

With the Amazon-ification of Whole Foods, not to mention the push for human interaction-free shopping experiences, the fact that a market like Gus’s continues to grow and thrive is something to celebrate.

“Not to judge, but they’re building platforms to disconnect that one-on-one interaction with customers. We’re trying to keep that connection. That’s why it’s so important to us,” says Dimitri Vardakastanis. “You can go online and order groceries with us as an option, but what we really hope and want is that (customers) come to the store. Come meet the fishmonger, come meet the person running the deli, or anybody in the store. Chances are, that person is part of your neighborhood, your community. Not only do you get to buy your fish, you also get to interact with somebody within your neighborhood and city.”

“That is more important than just buying groceries in our mind.”

That said, without the competitive nudge from larger national retailers, Gus’s might not be the market it is today.

“I feel like competition makes good business owners great. It forces you to get to that next level,” says Bobby Vardakastanis. “When Whole Foods moved into the Haight, (it was) our opportunity to show that we can also provide full-service just like any other Whole Foods, Safeway or whatever larger chain stores can offer.”

Sure, Gus’s keeps up with its competition by catering to modern San Francisco shoppers, but the real draw remains that each location serves as a touchstone for the neighborhoods they serve.

That community investment was nowhere more evident than in the days following their father’s death, when impromptu memorials blossomed in front of their stores.

“Having community in a name, it all kind of came full circle. We saw it not just on a consumer level in the store, but on a larger scale,” says Dimitri Vardakastanis. “Nothing lives on our dad’s legacy more than expanding our business and keeping the kind of legacy alive. We’re happy to be pushing forward and opening this new store — and having his name on it.”

Sarah Fritsche is a San Francisco Chronicle staff writer. Email: sfritsche@sfchronicle.com. Twitter/Instagram: @foodcentric