Its a bit tricky to get started from what I have seen. I don't see the numbers too much, but what I have gleaned is to start smaller, like you said with phasing. still risky, and definitely like most new businesses you need to be able to survive without earning much if anything the first couple years.
and it can be a chicken and egg thing, meaning you need people to draw in businesses, but you also need businesses to draw in people. so it helps if there is already something nearby, walking distance. having a few "anchor" tenants will be key too. a grocery store being key to the area.
unless you have a state/national park nearby and can rely on short term leases people are going to want a grocery nearby. you don't need a full size publix, one of these small sized guys would be perfect if there isn't something in the area 5-10 minute drive.
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small convenience type retail/bodega type places would be good starters too.
access will be key. Not just to amenities or healthcare as pointed out. but can you get to the interstate quickly. is there another population center nearby, or are you near a major highway. going the full blown small town, isolated feel requires luck and dang good connections, because you will only have word of mouth.
restaurants you want a mix, you want a sit down type place that has a liquor license, or at least can sell beer and wine. and then you will want something for people to pop in and out of for lunch type meals or coffees.
having places to hang out, a lawn with seating, covered patios, or just outdoor seating will be key to activate the place. parking key too, even though you want the walkability, nearby parking is going to be key for business. you never want the place to feel empty, even if you are doing phases. find ways to activate the empty lots. pop up stores, farmers markets, food trucks, temporary beer halls. to be frank you are probably going to need to appeal to ladies to make it some place they will drag their +1.
pure guessing but you probably need about 10,000 of retail/restaurant space to start. I would say about 5k is restaurant, split to something like 3500 for the main sit down place, and 1500 for the pop in place. then divide the retail into small retailers, sans grocery. 1k to 1.5k per. mini-malls do great, lots of small stores, again you want to drive interest and activity. these are bigger, because they are in atlanta but things like Krog Street Market, Avalon, the Works here in Atlanta do crazy business.
www.thekrogdistrict.com
theworksatl.com
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Office keep small. maybe just over the bigger restaurant, as that is going to be lower rent for residential anyway. and generally there isn't a huge market for office right now anyway. the We-Work type set up, or some type of combo use place is going to be key, again you want to drive activity and interest, and not just rely on one big tenant unless you already have a whale.
residential a couple things will be key. Townhome living, over retail, isn't for the old empty nesters usually. they will want ground floor access, elevators, and will get tired of the activity. so private residential areas away from the active front will be key. something that gives the community its own space while having access. think of something like rear alley access to the retail, with controlled access. small tables, lights, more comfortable than the active front. maybe bar access to the big restaurant from the private area, so people can grab drinks without dealing with the tourists. don't do anything more than 3 stories without an elevator, access to the units will be key to determining the vibe. is it really residential over retail? Do you want them to feel more separated? Are they just some townhomes or tiny homes behind some retail with some type of cutesy space to tie them together. is it more the neighborhood feel, with clear separate residential, and just a small defined separate retail area.
Serenbe is a smaller town vibe place that has had great success. but this was built over decades, and really only survived because it was the rich hippies getting out of the city.
The best reason to live here is the life here. Serenbe is a pioneering community model connected to nature on the edge of Atlanta.
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