IMHO it depends on how much flammable material is near the home, if a raging fire could approach, then evacuation is the only sensible option.
On the other hand if the surroundings have been kept clear of any build up of flammable junk, then as others point out, the risk is from radiant heat and burning embers.
If the radiant heat is not close, then it is survivable, and small fires started by embers can be extinguished.

A garden hose fed from a well or city water supply is better than nothing, but not IMHO realy sufficient.
Consider the risks of the water supply failing, or the power to a well pump failing.
A portable engine driven pump, and a large water source such as a swiming pool would be better.

Proper planning should consist of clearing away flammable rubbish, shrubs, trees, outbuildings etc.
This will limit the heat produced in the imediate area, both reducing the risk of fire spread, and making staying for firefighting less risky.