If its a pre-employ, you probably won't be observed. Find a clean donor or get some Quick Fix 4.0, and practice, practice, practice. (Make sure you get the temp right). Hide that bottle in your sweet spot (wear a couple of tighty whities) and warm it to body temp, but you have to practice with the temp (I've heard the forehead temp strips work well).

Don't ditch the bottle in the john wastebasket, because I'm sure it's searched.

Don't know how long you've been clean, but if its only been a few days, chances are dilution won't help you. There are ways to dilute on older threads on this board.

As for your "all white" tests, you may be using them incorrectly or they are defective. Don't shove the entire stick into the pee, but just the bottom.

You can order the Specimen Validity Strips by doing a google search. Don't know how many home tests you have left, but if you have time, order some off of ebay and keep experimenting with dilution.