Amazing friends!!!

Ok so we have a church group we hang out with, its a young marrieds group we get together have dinner let our kids play we all pitch in with a dish and we do games or we have an experienced couple come and talk about their lives. Anyways there's a couple we love but haven't had much one on one time with but they still did something incredible for us. My husband and I are living pay check to paycheck barely making ends meat sometimes I have to put a bill on our credit card then pay it so it counts as our credit card payment and the bill payment, eating hamburger helper like 20 days of the month

And then my husbands care broke down on his way home from work, we posted on Fb if anyone would be kind enough to tow it home for us as we couldn't even afford a tow truck, our friends said they were more than happy to do it for us, when they got there they called and said hey so "Adam" (not real name) went to school for mechanics and he works at his parents auto shop we have the tools at our house mind us taking it home to look it over for you? And I'm like go for it! That's amazing. So sometime later "Kathy" calls and says so this is what's wrong Adam found the part he's gonna get it fixed tomorrow, so I asked how much it was and she wouldn't tell me just said 'paying it forward!' I'm crying and she's saying its no big deal then a couple days later calls and says they fixed that issue but found another and are waiting on that part and still refuse any money knowing our situation. I'm amazed at the generosity it takes to put all that time, effort , Money into a problem that isn't yours and not expecting anything back!!

So my question is what can I do to show my aporetciation, to show just how much this meant to me and my husband? They won't accept money and we can't afford hardly anything but it feels wrong to not do something!