Homogenizing Vaporizer Cartridge Solution

Recently I purchased buddy e-cig style vaporizer and decided to stop buying pre-filled cartridges of concentrate and just fill my own. I went with a wax/propylene glycol solution and that seems to work well but I noticed that after a day or so of sitting still it started to separate. I know one solution may be to use a higher quality concentrate but does anyone have an idea for stabilizing the solution?

A single drop of alcohol seemed to help everything dissolve completely, but like I said after a while it needs shaken back up.

We were able to fully homogenize our solution, using a CAT Scientific X-120/17(N) homogenizer. It turned it into an emulsion, which remained perfectly stable for over a week so far.

While I'm inclined to agree that a handheld homogenizer would be the best route. Would you be able to provide a solution that's initially a little more cost effective?