who to get in to fit dishwasher?

Do white goods engineers just do repairs? Or do i need to get a plumber in to do the initial installation?

I have a table top dishwasher and need to get some help really with this. Partly because it’s heavy and will involve moving the washing machine to put the cold water hose behind. Also the dishwasher will go slightly over the draining board and so I need someone to be able to fix up a piece of wood for it to stand on to be level. And also to fix the drain hose over the sink so it doesn’t move everywhere. (or get a really long one to reach under the sink.)

Any advice on who to call?

Thanks

(and on a totally unrelated matter, but saves another thread do those anti frost mats (to putin freezers) work?)