There are lots of cheap enlargers out there, so no real reason to cobble something together.

That said, the largest enlarger I have room for in my little Manhattan apartment is a medium format enlarger, so for 4x5" I use a Graflarger cold light back on my Linhof with a copy stand, and it's pretty good. The Tech V is rock solid, and I can use the camera movements for small perspective corrections when enlarging. I use a conventional enlarging lens mounted on a Linhof lensboard.

In any case, you can find Graflarger backs that will attach to any 4x5" camera with a Graflok style back for under $125 usually. Aristo will even upgrade the tube for around $100.

For larger negs than that, I contact print, though I could rent darkroom space if I wanted to enlarge from 8x10".