In Puja and Homa you have no restrictions. These are basically purposeless and just for devotion. A result is normally not expected after these Puja and Homa.
The most important is that the mantras chanted in a puja is like 1 time or 10 times or 108 times or 1008 times while in Yagya the quantity is 25000, 51000, 125000. Naturally the Puja and Homa (hawans) are done by one pandit in 1-3 hours while a Yagya with 125000 chanting takes 5 to 31 days depending upon the number of pandits like 3 or 5 or 7 or 9 or 11. A result of Yagya is normally expected.
For a puja or Homa, the pandits in India are normally paid from Eur 5 to Eur 20/ or equivalent while the cost of Yagya goes much higher in that ratio and therefore not everyone can afford Yagya very often. More.
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