Concrete Ceiling - Load bearing walls?

[Peterpan101]

Hi, I am looking for comments regarding the basis of the walls in this one storey flat roofed building which is attached to a Victorian property built 1888. The ceiling is concrete and I want to open up the area, taking out the small brick walls between each of the utility rooms. I suspect the only load bearing wall that I would like to widen is marked A on the plan. However, I am unsure as to whether the other walls B and C are load bearing, given the concrete ceiling. The builder I have asked is none the wiser and neither is the non-structural surveyor, on his initial visit.

The surveyor (non structural), wants to charge me £2K to draw plans (and does not include even include a structural survey which will be needed), to then submit to the building regulators.

If after the structural survey, the structural surveyor simply states a reinforced beam will be required to replace wall A, then the £2k charged by the non-structural surveyor is a lot of money; just to draw-up this basic requirement into a plan.

However, if the structural surveyor suggests a lot more needs to be done to support the ceiling in light of the removal of the other walls, then £2k might be worth it.

I plan to engage a structural surveyor prior to agreeing to the non structural Surveyor's services.

I would appreciate your thoughts on the construction of this building and whether the smaller internal walls are likely to be structural or not, given the concrete ceiling. Many thanks