To Sell a House Spell

As with any magical working, the first step is to do the mundane work:

List the house with a good agent, clean it from top to bottom, put a sign out front and an ad in the paper, and tell everyone you know that you're selling it.

Assuming that's done, begin your ritual by obtaining a Green Candle.  Green was a traditional color for prosperity spells long before they decided to make U.S. currency that color:

It symbolizes a green and fruitful harvest.

Now, go outside your house to some spot where you can see the house but not be disturbed (standing in the middle of the road is not recommended).

 It's best to do this at a time when the street is relatively quiet. If possible, face the house from the same side that a prospective buyer would when seeing it for the first time.

 Sit or stand comfortably, holding the candle.

Close your eyes, relax and take a few minutes to begin breathing regularly and establish your concentration.

 (If you've ever done regular meditation or prayer,
establish that same frame of mind.)

Now visualize the house through a stranger's eyes.  In your mind, envision brilliant sunlight, whether it's there in real life or not.

Mentally walk from the driveway to the front door (or whatever entrance is closest), then into the house.

As you do this, envision the house as the most beautiful it can be. If the paint is clean and white, envision it positively gleaming. If there are plants in the yard, envision them not just thriving, but seeming to beckon the passer-by, reaching their
little green selves up into that same brilliant light.

In your mind's eye, walk through the entire house with the eyes of a stranger, dwelling on every good point it has. Do not let thoughts of its flaws disrupt your  Concentration (this is the tough part).

That same brilliant sunlight pours through every
window and door. See it fill up each room as you enter.
When you have been through the entire house, go back the way you came.

 Envision the light from each room pouring into your mind, through your body, and out through your hands into the candle.

 Like a battery, the candle will absorb this light energy.
Take a few moments in each room to let this happen.

(There's a lot of light; it won't
diminish in the room when it pours into you.)

Now mentally go out through the same door and stand in the driveway, seeing the house covered with brilliant light. Again, feel the light that surrounds the house pour into you,
and from you into the candle.

When you're done, continue to sit or stand for a few moments with your eyes shut, and let any excess energy that remains in your body flow naturally into the ground.

Then open your eyes. Light the candle at an appropriate time - the night before a showing might be good.

A Witch would probably wait for the Full Moon (a time of bounty) or the first Quarter Moon (a time for new beginnings).

An astrological magician might do so on a Monday (the day of the moon) or a Thursday (the day of Jupiter, the Bestower).

As you light the candle, intone the words of the spell:

"Fill my home with energy, that it may bring me prosperity. Light and beauty fill my home, That its new owners soon may come."

Let the candle burn all the way down. (I hope you didn't get one of those 15-hour ones!)

What this visualization does is to fill the house with positive energy. Buyers respond to this energy whether they're aware of it or not. By dwelling on all your home's good points, you've filled those places in the house with special energy so they won't be overlooked.

Also:

Before each showing, subtly scent the house with Cinnamon  Incense, Potpourri, maybe one of those lamp rings. Besides being a prosperity herb, Cinnamon's aroma makes people think of home cooking, which will make them want to settle down there.