Sleeping at night. 9months

I really need advice and help on what I am to do with my LO. Everyone tells me to NOT have your baby sleep with you at night bc you can roll on your baby or you will have that much of difficult time getting them in their own bed when they are older. Me and my babies father are not together, she is with him every Wednesday and every other weekend. When I get her back her sleep pattern is always off. At his place she sleeps with him and not in her play pen (small house no room for her own crib). She can't sleep through the night in her playpen so they (him and his mom) moved her to the bed. There she sleeps through the night knowing the comfort of them being next to her. At my place she sleeps in her crib fine wake up at 4 wants to play and then I feed her she goes back to sleep. I assume this is a growth sput. However, on the Sunday nights I get her back she wake up every hour on the dot in her crib and I do not pick her up but put her back on her tummy and she quickly falls asleep. I guess my main question is, is there a problem with letting your LO fall asleep with you in the bed? Is it that much harder when they are older? I know she probably can not handle the back and forth, plus she is teething. I am just at loss of what to do because when I get her it takes me 3-4 nights to get her back on schedule everytime. PLEASE HELP!!!