How to convince my neighbors to sell me their house?

[Jonathan Thrasher]

So I don't know why this didn't occur to me until today but I had an epiphany. My neighbors have spleen saying they want to sell their house for over a year now.  The other day we were talking again and he told me how much they owe on it but said he has a lot of work left to do on it before he sells.  So it occurred to me today, why don't I try and buy it?  This would accomplish a few things.  Give me my first income property, potentially increase my property value and best of all, get rid of my neighbors and their annoying super loud motorcycles.

I know the house needs exterior work.  Probably a new roof, and definitely siding.  I have never seen the inside.  I know from talking with him that he thinks his home is worth way more than it is in its current condition.  So....how can I approach him?  Obviously I would need to see the inside to get an idea of how much really needs to be done.   Then somehow make an offer that isn't offensive and helps him not have to do any more work. 

Thanks for any advice!