Creating Unit trigger

Im having trouble with one trigger . Here is what im trying to make

--Event--
Every 140 seconds

--Condition--
Player Neutral hostile controls no bandit lord in region "x"
Player Neutral hostile controls no bandit in region "x"
Player Neutral hostile controls no rogue in region "x"

--Action--
creat 1 bandit lord in region "x"
creat 3 bandit in region "x"
creat 2 rogue in region "x"

now to me it sounds easy but since this isint starcraft triggering then its not easy. Pretty much all i need to know is how to do the conditions mentiond above. Thanks.

the condition you want is a BOOLEAN COMPARION -> UNIT - UNIT IN REGION EQUAL TO FALSE

Well it coudl work kinda but here is the thing, i want it to be a specific kind of unit not a unit that is already placed. like i dont want it to be

if bandit lord 0090 is not in region "x"

i want it to be

if a bandit lord is not in region "x"

i hope i explained it enough and thanks raven for atleast geting me started.

Just do a check like so:

Pick Every Unit in Region and do(
If Unit (picked unit) = Bandit, then (Set Variable[boolean-Bandit] = true) else (do nothing)
If Unit (picked unit) = Bandit Lord, then (Set Variable[boolean-BanditLord] = true) else (do nothing)

and so on... and then...

If (boolean-Bandit = False) then Create 1 Bandit
If (boolean-BanditLord = False) then Create 1 Bandit Lord

and then..

Set boolean-Bandit = false
Set boolean-BanditLord = false

And so on.

:) That WILL work, though it's a bit messy :/

than just add another condition, a UNIT-TYPE COMPARISON