How much and what kind of equipment is going to be determined by your menu (the sheeter is great for rolling dough - cookie dough, tart dough, etc. but if you are only making cake, you wouldn’t need that).
Your local board of health can help you; your state dept of health can give you food code requirements as well. You would also want to check with local zoning requirements; in some places you cannot run a certain business from home without a variance. You would need the variance first and in some cases, you must be operational within a year of getting the variance or it can be revoked. Someone who handles real estate law in your town could probably help you; find someone who knows the ropes of zoning board policies to help you navigate that mindfield.
You will also need to take the Certified Food Handler/Manager course - your local BOH can give you a list of places that offer the one-day course, or maybe divided between two sessions. You’ll have a lot more credibility with the BOH if you have that certificate first
In many places, the BOH won’t make a distinction between a kitchen in a private residence versus a kitchen located elsewhere - you will have to follow the same requirements for sanitation and storage (a separate hand wash sink, multi-bay wash/rinse/sanitize sink that can handle the largest item you have be it a sheet pan or a 20 qt mixer bowl, and a mop sink - you also have to use copper piping, no PVC. Your local BOH may require a grease trap, which requires cleaning on a regular basis.) Buying used refrigeration is usually a problem so that’s definitely one thing I’d buy new; just about everything else can be found at auctions or from a used equipment dealer. Find someone who can offer you some sort of warranty on the bigger items if you by from a dealer. Otherwise you’re buying as is, and with used equipment you never know.
Perhaps you can tour some businesses or kitchens in your town to get a feel for what and how they are set up.
I’m sorry; I didn’t read your initial post carefully enough to realize you are in a foreign country where the rules are most likely dramatically different from here in the US! Much of this information may not apply to your situation.