#1 appears to be a dracaena godseffiana. #3 is a syngonium podophyllum "White Butterfly" I think that #4 is a sansevieria trifasciata hahnii "Lucille Polen". It almost appears to be either a sansevieria trifasciata hahnii "Gold Flame" or a sansevieria guineensis " Variegata" but I think it is a "Lucille Polen" Here is a link to a catalog( no endorsement implied) http://www.glasshouseworks.com/succ-s.html with an amazing selection of sansevierias. #2 is a toughie, it might be some kind of peperomia, possibly peperomia campylotropa, although the leaves sort of remind me of romanzoffia......
#3 looks like Hyrdrocotyle tripartita to me. It's common name around my region is Kurnell Curse. It's an invasive weed and terrible hardy. As a house plant, you are probably watering it too much
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Jonathan Garner maih
NSW Counciilor, Australian Institute of Horticulture inc
Something looking very like#2 grows wild on stone walls in the Snowdonia area of Wales where I live - sorry but I don't know what it is called, but I will make enquiries locally if that is any help. Regards - Maggie