Certainly enjoy the milestones along the way.

We're a newer company that's still small yet we've hit a milestone.  

@Nat Chan I never understood why contractors would ask for a large deposit to start a project, here in California your limited to what can be asked up front generally up to $1000 or 10%, which ever is less.I never give deposit, most contractors that we deal with have a clear and well define scope of work, attached with a detail schedule of values (Especially for large projects that run a couple of months) and a construction schedule complete with milestones.

This is a true rags to riches story that we can associate with at BP and have proof that it's doable.We look forward to hearing about your future milestone achievement as you happily work towards your 4,000th posting.

Congrats on the milestone!

Consider the value of preferred payouts for milestones or risk points.Entity?

Mostly, after the first small down payment, subsequent payments are based on milestones of task completions. 

Make sure you have written out in a contract all of the work you expect to be done (this cannot be to specific in my opinion) and the payments schedule/work milestones timeline agreed upon upfront to avoid any confusion down the line.

hard to say which part of this was the closing of the deal, but to me signing of the lease was the milestone.

Additionally, if you do choose to use a GC, make sure you have a timeline with milestones in place up front.