What would you do?(sorry it's long😳)

Michelle💋
My boyfriend and I are selling his trailer since we can't live there. We can't get power turned on unless we pay $3000. And it wasn't his fault. It was his uncles for stealing power when it was off-the power was NOT in my boyfriends name. Anyways. We got a house were renting in the same town as work and school as i cannot do school work without power. And he doesn't have an hour long commute anymore. So the people buying his trailer are drug addicts. They don't care there's no power right now. They told us they'd give us $200 every 2 weeks. So far they've only been paying $100 every month. My boyfriend texted them today and asked when they would pay us again and how much. They said "we can only give you $100 this week. But next time we can give you $400, I promise." And he said "okay we'll swing by and get the $100 tomorrow" and they responded with "oh well, we can't pay you 100 because we have bills and we missed work and we need groceries. We can give you $200 on the 7th. I promise." I told him he needs to tell them to give us 400. And to stop playing games again or we will kick them out again. (the only reason we are selling to them is because they are the only way we can get rid of it. And they've fucked that trailer up so much. Dog shit. Cigarettes everywhere. It's the definition of trailer trash) what would you do? Take 200 or tell them to pay the 400 like they said at first? I mean I think he's just taking the 200. But I think he needs to push for the 400. I just don't get why they'd offer 100 if they couldn't pay it.