We have gateposts that are likely built from masonry blocks. The posts were plastered about 15-20 years ago, but the plaster has now started to crack and fall off. We want to refresh the posts properly but are having trouble finding craftsmen for such a "small" job, and we know absolutely nothing about concrete, plastering, etc. Today, we knocked off what was loose, but we hear there are other areas that should really also be knocked down.
The worst part is the holes/corners that need repairing. The deepest are 7-8 cm. We have been advised to use Finja C or Finja spackel for outdoor repair, but we're unsure if we need to start with something harder, like Finja A, because the holes are so deep. Is adhesion necessary? How many layers should we apply?