BIG TIP:  Make sure the sand you use is DRY.  I bought Five 50lb bags of sand, and unfortunately only one bag was totally dry, the sand in the others was moist from being stored outside and it made the process a LOT longer as the moist sand doesn't flow through the funnel as smoothly and turned what should of been a 60 minute project into a 3 hr project.  No hard, just time consuming.  Have a little water standing by, and as you fill it up the DRY sand, add a little water AFTER you've put sand in to give it a little extra weight.  These things are heavy and I'm expecting them to hold the umbrella is some wind.