Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 9 · Vastu, Griha Pravesha
वास्तु गृहप्रवेशश्च
खरोश्वोथ हरिः श्वाख्यः सर्पाखुगजशाशकाः ।दिग्वर्गाणामियं योनिः स्ववर्गात्पंचमो रिपुः ॥ ५६० ॥
In the full Narada Purana (Purva Bhaga) this is chapter 56, verse 560.
The ass, the horse, the lion, the one called dog, the snake, the rat, the elephant and the hare. This is the yoni (animal match) of the direction groups. The fifth from one's own group is the enemy.
Simple meaning: Each letter group has an animal. The fifth group from your own is your enemy.
साध्यवर्गः पुरः स्थाप्य पृष्ठतः साधकं न्यसेत् ।
Compare the letter groups of the place and the person. It is good when gain is more than debt.
आरभ्य साधकं घिष्ण्यं साध्यं यावच्चतुर्गुणम् ।
Count the stars from the person to the place, multiply by four, divide by seven. The remainder shows gain.
विस्तार आयामगुणो गृहस्य पदमुच्यते ।
Multiply breadth by length to get the area. Six figures are worked out from it.