Newsflash: My cousin’s kid is interested in my late mom’s house. Should I tell their realtor that we aren’t going to put it on the market and that we’ll let them have it or wait until we talk to an attorney?

So it’s been back and forth for the past month. My cousin told me that her son and his girlfriend were interested in my mom’s house. They came and looked at it with their realtor while I was out there for my mom’s funeral and they REALLY liked it. We asked what their upper limit was and they said $350,000. I told them that I’d let them know what we’d ask for it after the appraisal.Well the appraisal came in at $355,000 which I relayed to both their realtor and them. The realtor replied the next day with “They are very interested” What are your thoughts on the purchase price?” I told him that we’d sell it to them for $350,000 since that was their upper limit. Well at the same time they had to leave the state for 3 weeks for Nat. Guard duty and would make a decision when they came back.Well during that time my sister said that we should put it on the market to see how much we could get for it. I said ok but felt bad that I told them they could have it and now telling them they can’t. I relayed to their realtor that we are now putting it on the market but for them to please place a bid. Then I told my sister that it’s silly to put it on the market if they and another party are interested in it. So then we thought we’d just have both parties place a bid, but we hadn’t told them that yet. In the meantime I contacted a friend’s brother who is a broker to get some advice on how to proceed. It’s been over a week and still no answer. My friend said that he got the email but has been busy. Well yesterday I convinced my sister to just let them have it for $350,000 because I’m tired of waiting to get an answer and want to be rid of the property. I asked my friend to now relay to her brother that we are going this route and just wanted to ask him a few questions like “Is it ok to say we are going to sell as-is? Also if we can request that they take care of all the closing costs? I want to wait to get answers before telling them but I also want to get an attorney to help us through it. I just don’t want them to end up finding something else and not wanting it after we hire an attorney, which is why I’m wondering if I should let their realtor know that they can have it for $350,000 but we are still working some things out and will approach them about it after we get some questions answered? The realtor sent me a message early last week saying that he told the guy what we were doing and he was bummed but they understand and to let him know if something changes. Is this something I should let the realtor know, but not give a lot of detail yet?