I am wanting to have built or to build a pole barn garage about 30x30.
I have been working the ground with a power tiller and a tractor. It
is alot more level than it was but still has some low spots. Is there
a good way to ensure this is level?

Is there anything out there not too expensive that I could make or buy
that would help me get this as level as possible? (Short of buying a
200 buck transit). WOuld a laser level on a pole work?

Also, would it be good to put down gravel before poles or anything go
up? (Not sure if I can afford concrete or not yet. Looks like the
gravel first would provide some protection for the poles when they go
up if it rained on the bare dirt which would cause mud splashing up on
them.

Any help is greatly appreciated!