Sleep for mom and baby help!!!

I am a single mom of 3. My youngest who is 8 months on January 12th is the only baby I fully breast fed. When he was born he had a tongue tie so it was rough and they had me feeding him in demand and then he had his cluster feeds. So he was in my arms a lot from birth till 1month once he had his tongue tie fixed.. but he had done became use to being in my arms at all feeds and in sleep.. now I can’t get him to sleep to sleep unless he is in my arms and sometimes I can barely get him in his bed at night because as soon I lay him in his bed he wakes and won’t sleep. Some nights I get him to sleep in his bed but most nights he’s in my bed or no one gets sleep. And I woke full time so I rely on sleep to function. Moms I’ve tryd the let him cry it out but I can’t at night bc the girl upstairs will file a complaint or call CPS. (She is mad I got the downstairs apartment she wanted) please help