Hi Edgar,
First, congratulations on becoming the owner of a coffee bar. Where about is it, please?
My first response is to go get yourself hired at some coffee or fast food place, at least for a couple of weeks; the guys and galls running one are experienced, make use of that opportunity to both learn how you shape up behind the counter and see how things are done.
Before one can answer your question please provide some info :
1/ How did you acquire the bar?
2/ Do you own the building and the land under it, or did you take on a lease?
3/ Is there currently a coffee bar in the building?
4/ Is the interior / fixings and fittings as you'd like to run the bar, or will you need to refurbish?
5/ Would you need planning approval / zoning consent?
6/ Do you have adequate cash / line of credit to cover pre-opening outlays and first months wages / running costs?
Once you've answered that we'll have some idea whether it'll be feasible to run a coffee bar there in the first place:
a/ How many coffee bars are there within say six minutes' walk from your bar?
b/ Why did the previous owner seek a new owner (retired/ died/ jailed; bankruptcy/ divorce; change of interests?)
c/ Take it from your question that you have no experience running a coffee bar, not even worked in one?
d/ What is your line of business / nature of your employment? Why leave that work? Approximate age?
e/ Experience running own business, including financial/ accounting and food hygiene aspects?
f/ Who will be working behind the counter? Serving at / taking away from the tables? Family? Hired hands?
Once you answered these questions you'll have some idea of economic feasibility.
g/ Your guests will likely want to eat something : croissants/ sandwiches/ something chocolaty/ cakes.
h/ Do you intend to serve a light lunch? You'd undoubtedly also serve tea, hot cocoa and mineral water?
i/ Is seating limited to high stools at a bar, would you have room for small tables, comfy chairs?
j/ Is there a patio in the back or an option for pavement/ sidewalk seating? Something to shield from sun/ rain?
k/ How do your family and friends think about your venture? Are they able to offer support when needed?
Now that you have made an inventory of what you're going to offer in your coffee bar - it may in the end not become a coffee bar, instead you may evolve into a gap left by others in your neighbourhood - the one big and I mean really huge question is whether you have what it takes to make the bar a success.
Think of a kind word to those early morning customers who are in for a chat, or just a friendly nod to the ones who come for a quick coffee. How do you respond when a usually cheery customer comes in with a gloomy face?
Many coffee bars have the larger equipment placed along the wall, the counter staff working with their back to the customer while operating it : apart from the image you project when all goes well, think of the image your backside presents to the customer when you're rushed, or when things go different from how they should: perhaps you just dropped your last pastry, or the coffee maker spills it all onto the floor : there is so much your customers have all the time in the world to observe while you're working your butt off. As a customer that - together with the ambiance, smell and taste of your coffee - determines whether I'll be back, and back, or ...
Coming back to my opening suggestion : apply for a job at a coffee/ fast food place to gain an insight in how you're likely to bear the pressure, deal with irate customers, respond to a rush. They're often quite happy to hire: there is a surprisingly large turnover in staff and they'll frequently take on anyone who can be made to look presentable.
What if none of them will hire you? Well, it could be their error of judgement, or it might be a clear indicator : hard to say, because circumstances vary by region and even by area within a city.
May I wish you all the strength and wisdom : you'll likely need lots of it.
Good day to all. I'm a new coffee bar owner. I just want any ideas from you guys here if you know something about coffee bar. Is it a nice idea to or too expensive? Any opinion would be great! Thanks.

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