1 last step for me to craft construct. I need help.

[Veilgn]

1. I confused about :special ability. I dont know about it, is there a list for this "special ability" for construct ?

2. How to calculater final cost for special ability?

3. Some special ability able to reduce CR. I need that for cheapen the construct.

Any help will be appreciated. I also can help my friend to craft construct too.

[Veilgn]

Do fly considered special ability?

For hiw many feat if do?