Remove tile adhesive from the floor

I want to have the bathroom floor covered with click vinyl or tiles.
I have already removed the tiles.

Now I want to have the adhesive removed by a company. See: photo

1) Do I need to make sure that the adhesive residues from the floor tiles are also removed under the wall tiles, or is it only laid up to the start of the wall tiles? Since it is finished with silicone, the spot is not visible.

2) How much does this usually cost? It is 4 sqm.

Thank you

2) How much does the job cost approximately? It is 4 sqm.

That will be difficult. For such an unprofitable job, you will probably have to take whoever is willing at all. It can quickly become several hundred €.

1) Do I have to make sure that the adhesive residues of the floor tiles are removed under the wall tiles as well, or do you only lay up to the start of the wall tiles? Since it is finished with silicone, the spot is not visible anyway.

Either you lay the floor tiles up to the edge and then put the wall tiles on top (normal) or vice versa. In the end, you only see the silicone joint. Since hardly any tiles will be pushed under the wall tiles in your case, the residues can remain.

This will be difficult. For such an unprofitable job, you probably have to take whoever is willing at all. That can quickly add up to several hundred €.

At €150.00 that would be okay for me. If that is not feasible, there are alternatives.

1) The rental machine would cost around €100 per day.

2) The cheapest renovation grinder found on the internet would cost €89: Matrix MT 1100.
It should withstand 4 sqm.

How long does the sanding take approximately with a simple renovation grinder by a craftsman who is a beginner at these tasks?

What would you recommend?

Either you commission the tile laying, which includes removing the old adhesive, or you do it yourself. No one will come just to scrape off 4 sqm of adhesive.

You had asked recently already
https://www.hausbau-forum.de/threads/bodenfliesen-sind-entfernt-wie-die-spachtelung-entfernen.38949/page-2#post-491036

How long does the grinding approximately take with a simple refurbishment milling machine by a craftsman who is a layman at this work?

With the rotary hammer, depending on the condition of the adhesive, about an hour or two. I wouldn't use a milling machine for that. Maybe just take a hammer and chisel.

I would also try with hammer and chisel. You can definitely do that yourself. And the leftovers that don’t come off completely, you can surely work on them with a concrete grinder, right? Something like in the attachment, doesn't cost the world, you just need the right angle grinder.