1. Villa ( the one that allows you to return to your action phase) ,official FAQ says it does not trigger "Start of turn " abilities
Since there are cards that trigger on "Start of turn" and "End of turn" , then should there not be 2 extra phases in a turn?
Like a Start of turn phase and End of turn phase?
So it would like something like this:
Start of turn Phase
Action phase
Buy phase
Clean up phase
End of turn phase
Would this make sense? If not why would it not?
Thoughts regarding this?
It
kind of makes sense, and it can be helpful to think of it that way when you're keeping track of when things happen; however, it's important to remember that the "start-of-turn phase"
is technically part of the Action phase, and the "end-of-turn phase" is technically part of the Clean-up phase. For example, Patron gives you a Coffers token if you reveal it during the Action phase; if something causes you to reveal a Patron during the start of your turn (e.g., Piazza), you do get the Coffers token. It's not a separate phase.
Question 2. The buy phase in Dominion states something about once you buy something , you can't play anymore treasures from your hand.
Does this only include spending coins on cards , events and projects? ( basically anything with a cost on it in the Supply) or is there other things?
Well, you don't always have to spend coins in order to buy something. If you buy Overlord, you don't spend any coins, and you can buy Animal Fair without spending any coins as well. But basically, the answer to your question is yes; those are the only things that count as "buying" something, and therefore that end the portion of your Buy phase when you can play Treasures.
Question 3.
Example
I am in the buy phase with 1 copper in hand. I buy a card that returns me to my action phase (like Villa ), still having the copper in my hand , then I return to my Buy phase again in the same turn.
Since I am at the start of the buy phase again in the same turn , can I play the copper from my hand now?
Yes, it's now the beginning of a new Buy phase, so you can play Treasures again until you buy something.
Question 4. If I can't play any more treasures from my hand once I buy a card , can I still play Action cards from my hand during the buy phase even after I bought one card already?
Ordinarily you can't play Action cards from your hand during the Buy phase at all. You can only play an Action card from your hand during the Buy phase if something specifically instructs you that you may do so. If something happens after you buy a card that instructs you to play an Action card from your hand (for instance, if you gain a Gondola), then you can play an Action card at that time.