Vishnu Sahasranama Homa is a vedic performance where Lord Vishnu along with Parivara Devathas, Dikpalakas and Kshetra Devathas are invoked in a divine Kalasha. Shodashopachara Puja is performed in detail to Lord Vishnu and all the devathas invoked.
Following that, homa is performed while priests chant the Vishnu Sahasranamam. Samit, Charu and Ajiya are offered to the Holy Fire in the form of sacrifice. Purnahuthi is offered at the end of the Vishnu Sahasranama Homa.
You can perform this homa on any day by pre-booking. You can perform the homa in absentia too.