I have Tamiya Acrylic thinner, but I rarely use it. Because I thin their acrylic paints with Mr Leveling Thinner.

And I have Tamiya Lacquer Thinner which I use to thin lacquer paints as needed.  And actually I have been refilling that bottle with hardware store lacquer thinner, so really it is cheap lacquer thinner now.

I also have some enamel thinner, it's a no name brand.

And I have some alcohol, I think it is 70%.

After reading the posts in here, and some more stuff online it sounds more and more like GSW and Vallejo are very similar chemistry. So I bought some GSW paints, and some of their retarder / flow improver.  Even their website hints that you can use their retarder / flow improver with Vallejo.

I believe my Vallejo paints are the brush on ones.