Actually, "Davies Removals" is a problem because we don't know what the original name is, that is, we don't know whether "Davies" is in itself a family name or whether it's intended to be a possessive.

And then, if it's, say, a family name, it may or may not take an apostrophe.

Example: Suppose there's a removal company owned by a fellow named Jones. If the intent is to show that this is the company owned by Jones rather than the other one that's owned by Davies, there are two possibilities. The preferable one is "Jones's Removals", but many will render it as "Jones' Removals".

On the other hand, the intent may not be possessive at all, and the parallel may be "Smith Removals", where "Smith" is rendered as an adjective. If that is the intent, the usage on the van would be correct.

Dave Oesterreich