[masraum]

Most wifi devices are designed to send a signal horizontally, with a little vertical. You may be able to get by with a good quality wifi device in the middle, or if that doesn't work, or isn't a viable option because the entry point is on the bottom floor, then you may want to plan for having something on the 1st and 3rd floors. The second floor will probably see enough overlap that you should get a decent signal there. Obviously, if you go that route, you'll need cabling between the 1st and 3rd.

At 2200sqft and 3 levels, I assume your place is fairly small per level, and maybe kind of a long skinny-ish rectangle of 3 floors? You may have better luck with having the antennas laying horizontal aligned with the short side of your place, so the signal spreads up and down and front to back (assuming side to side is the short side).