First, this is the B&W subforum, you probably want the color subforum...
1) You do NOT need Photoflo with the Unicolor kit. The stabilizer already contains a wetting agent. Do NOT wash the film after the stabilizer, it is the LAST step. If you think the wetting agent is losing its ability you could add a few drops of Photoflo to the stabilizer but it probably isn't necessary.
2) You can use it every day or not use it for a month. I mixed a kit in January and I'm still using it, 24 rolls done so far. Sometimes I go a few weeks without using it, I just keep it in a cold cellar.
3) You can use as little film as you like for testing. Since you reuse the Unicolor kit it doesn't matter how little film you process, you aren't wasting the chemicals.