A guest or a boarder isn’t always automatically yotzay with the host’s Chanuka lighting. He has three options. The best option is to light his own. Otherwise, he can rely on his wife’s lighting for the household back home. The third way is to give a peruta to his host and thereby become a partner in his lighting. (ShA 1 – MB 3)
If you aren’t sure that your wife will be lighting back home, you must see to it to light yourself. Concerning the berachos, only say them if you can estimate that your lighting will take place before hers. If you can’t, have someone be motzi you with the berachos. (MB 2,16)
Similarly – if you come home at night and find out that your wife already lit for the household, you might not have been yotzay. Light your own without a beracha. (MB 2)
If you opt to pitch in a peruta with your host, some opinions hold that the host should add a drop more oil than necessary for the half hour of burning. Also, if the host is willing to acquire over to you (with a kinyan) some oil for free. then you do not need to give him a coin. (MB 3 – ShaH 9)
