I agree with Richard.
If you do NOT get ALL the parts with the enlarger, you can easily spend much more than you planned.
This happened to me. I got a basic Durst L1000, but it was missing a bunch of parts (negative masks for the negative carrier, condensers, lens boards, etc). In the US, Durst parts are difficult to find, and when you do find them the parts tend to be expensive. I had to get certain parts from Europe. And there are some parts that I will have to make, because I can't find them. When you add up the cost of all the missing/replacement parts $$$.
Even a common US enlarger like the Omega D5, when you need to get missing parts, the cost of those individual parts (negative carriers, lens boards, lens adapters, etc.) add up fast $$$.
And of course you need the lenses for all the film formats you want to print. Again it would be nice if it is part of the package.
As much as I like the idea of a color head so you can simply dial in the MC filtration, if you are NOT going to print color, I would recommend getting a simple condenser head. The reason for this is maintenance and repairs. It is much easier to maintain a simple condenser enlarger than one with a color head. The extra complexity of the power supply and color head is just more things to break or go wrong. This is especially the case for enlargers where the manufacturer no longer exists or is out of the enlarger business (such as Durst and Vivitar). Although one can make an argument to get a "spare enlarger" to scavenge for parts.