AzureC

Yes. It is located at Cellia South in the house near the PK center.

I don't think so. Never found them.

It's also available at Blackview City's credit shop.

Unfortunately, that TM is only available for more than 5 credits at a pokemon center that I don't remember it's current location. It is better to burn 5 Credits, unless you plan to put that TM on more mons later on.

Nope.

There is none at the moment. Right now, the only way to know is by feeding friendship berries to that Pokemon, and if it says that the Pokemon adores you or that it didn't had any effect, then the friendship is at maximum.

Have you tried to lose either way, without sofresetting, to see if you ended up outside of the mission?

A house with a yellow Triangle above it.

You could breed Smoochum with a Ditto, you know.

Blackview City. It's a house with a Black Triangle.