Levelling Floor that's part tile, part concrete

[talia]

We've recently moved into a new house and our living room used to be a separate room and a hallway but the wall was removed. However, no work was done to marry the flooring between the two rooms. The hallway has old fashioned tiles (which aren't particularly even) and the rest of the room is carpet. The carpeted section is roughly the same height as the tiles, but not exactly. A strip of wood is in place where the two meet.
We want to carpet the whole room but without removing the tiles first if possible as that would be more expensive. Obviously the floor is not even at all. What's the best way forward?
We are totally not DIY people and would like to know whether we need a builder or whether a carpet fitter would be able to deal with this.
Thanks in advance.

 

[ree]

As always, pics would help.

Are both floors suspended or solid?

How wide is the "wood strip"?

Typically, a floor man or woman would do all this work. The tiles would be lifted and both floors exposed to reveal the condition and the levels.

 

[talia]

I will try to get some decent pics later and will post.

I understand that the floors themselves are concrete as the house was built in the late 1970s, and when we lifted the carpet section we could only see vinyl tiles.
The wooden strip is about 3 inches wide, and seems pretty solid.