Do you need to go back to brickwork when re-rendering a pebble-dash house

Our house is pebble-dashed and we are thinking about having it rendered. The house across the road recently had their house done. Their house was like ours, fully pebble-dashed, but they had the top half re-pebble-dashed and the bottom half rendered smooth. She said that it was a lot cheaper to have the top half re-pebble-dashed and the bottom half rendered smooth rather than the whole lot rendered smooth. Is that the case? I would have thought pebble dashing would be extra work as they have to render and then put the pebbles on, but I know nothing about rendering/pebble-dashing.

Also, she said it was much cheaper doing the half and half because scaffolding wasn't required, where if they'd gone for the whole house smooth rendered, it would have been required. But the house that backs on to me, they recently had their whole house smooth rendered (originally pebble-dashed) and I'm sure the guys doing it didn't use scaffolding. Just wondering about scaffolding as I know that is quite a big extra cost.

Also, if you do have your house re-pebble-dashed/rendered, do they need to hack off all the old pebble-dashing and go back to brickwork? My sister's neighbour recently had hers done and the guys doing it took it back to brickwork which brought about a massive issue as the brickwork underneath wasn't in a great state. So she had to pay £7,000 just for one wall to be rendered in this special kind of bonding.

 

quite a few questions there.
scaffolding or a mobile platform has to be used regardless.
rendering a house without it is not an option these days.
it is possible to render over pebbledash with modern coatings depending on your existing pebbledash.
stucco / smooth render finish is dearer than dash as it’s more technical and more labour intensive .
the same procedure applies and the same number of coats of render will be required whether you have a smooth or dash finish.
the correct way is to remove your existing render , come what may and re-render.