Any advice on long distance coparenting

Background: I dated my boyfriend for 3 years, we broke up, and he moved 3 hours away. We’re both young, I’m a live at home college student, he works full time and has a house. I found out I was pregnant with our son 8 months into my pregnancy. My ex wasn’t too thrilled at first but still wanted to be part of the baby’s life while maintaining the new life he built after our breakup. I have full custody of our son, but I drop him off at his parents’ house nearby every other weekend and he comes and sees him for 2 overnights. It’s been going ok, but I have two dilemmas. The first is that my ex recently started talking about taking our son to his house on the other side of the state every other weekend. He wants to connect with his son more away from his family, which I totally understand and respect. My only issue is that he wants me to meet him halfway (1.5 hr drive) on Friday nights for the exchange. I’m thrilled he wants to spend more time with our son, but I’m finding the situation really difficult because he wouldn’t be able to pick him up until after work on Friday nights (8:30ish), and I can’t really afford to drive 6 hours every other weekend (3 hours there and back, Fridays and Sundays). I want to compromise but the distance is making it really difficult. It’s a lot easier taking him to his parents house, he’s not even a year old yet. Hypothetically, if he were to move back I would consider doing 50/50 but I feel selfish to even bring that up. I want what’s best for our son but this arrangement is too much for me. Which brings me to my second dilemma. I’m a full time college student graduating next spring. I have an internship and a good job lined up after I graduate but it’s not paid at the moment. Aside from family support, my ex provides for our son but it’s always been inconsistent. I don’t want to go to court, I don’t think it would be fair to take half his paycheck for child support and make him sell his house, but I really need the financial support for our son. I budgeted his needs which come to about $125 a week (formula, food, diapers). My ex and I agreed that he would give me $400 a month to be paid in $100 increments every Sunday. Lately, I’ve been having to bug him to pay me on Sundays, sometimes I don’t get his money until Wednesday/Thursday and occasionally he comes up short ($50 instead of $100 for example). Now with him wanting me to drive 6 hours every other weekend, I’m not sure I could even afford the gas. I asked him for gas money but he thought the idea was ridiculous and essentially told me he couldn’t afford to pay for the gas. He also mentioned that it wasn’t fair because he pays for gas to drive to his parents and never complains. I’m not really sure where to go from here. I don’t want to be selfish but it’s hard to commit to driving on top of being a full time mom and student and unable to financially support myself and my child. Does anyone have any advice? Our son is so young and this is only the beginning of our financial/custody agreements.