Evenly distribute objects

Select one house

decide where you want the rotation spot to be

for example if you want it centre bottom of the house

then to make that spot easy to find

Object > Add Anchor Points

With the object selected

switch to the Rotate tool

to add the rotation point

hover the cursor over the the bottom  centre , until you see 'anchor'

then Alt Click

the rotate dialogue box will open

type in 120

and Copy

next, to repeat the operation  so as to get the 3rd house go

Object > Transform ;> Transform again

You could draw an equilateral triangle using the polygon tool and use that as a guide for the tips.

You can use Guide/Make Guides to convert the shape to a snap-able guide.

Take one house and rotate two copies 120°. Then recolour the copies and change their opacity.

Is that what you want to do?