Sizing my new HVAC system

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I have an 100 year old brick row home in Maryland. I want to get rid of my gas heating system and go electric for both heating and cooling. I am considering mini splits but all my quotes seem way overkill.
My Manual J indicates I need about 30,000 btu heating and 33000 cooling for the entire house, which is ~1800 square feet over 3 floors including a basement which I also want to condition.
My main question is can I get away with only one or two indoor units per floor? The main floor is fairly open, but the upper floor, which is closed off from the rest and I rent out, has a long (~30 feet) skinny hallway on one edge of the house, with rooms at either end and two more plus a bathroom in the middle.
My quotes have wall units (6 or 7k each) in the three largest rooms, but my square footage and need is so small that I believe I will have short cycling issues.

If I just put one unit in each of the end rooms, or one unit in the hallway, will I get enough get enough circulation (I do have ceiling fans) to heat and cool well without the middle rooms being hugely different from the rooms with the wall units?

Thanks in advance for the advice.


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Peace valley missouri
Your number don't seem right. What are u heating with now? Gas? Look what ur usage was in the last couple of years heating deduct water heater summer vrs winter for hot water. Ask your electric company if they offer a energy audit that includes a blower door test.
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