How can I get eave rafters cut flush?
There are many ways to do this and which of them to choose depends on many things including what tools are available and the skill of the person using the tools.

Back when I was a carpenter I would choose to use a reciprocating saw but this takes a decent level of skill to use to both get a good cut and also not hurt yourself. Upside, will cut through nails.


Alternately, you could use a good pull saw and do it by hand. This is more effort and slower, but the slowness will work in your favor because it will allow you to focus more on the cut than the tool. Downside, any nails will ruin the saw.