New supply line

[Judd Campbell]

The house I bought a few weeks back had Pex run throughout.  I do not anticipate any issues with that but the neighbor begged me not to turn the main water supply on as he said it floods his basement. My meter is about 10 feet from the front of the house (which is on a crawlspace)

I was going to do some exploratory digging with the help of two local laborers. The supply line is currently cast iron and I am just going to plan on replacing it with pex.  

I am planning on hooking it up to the supply and running it 36" deep until it gets under the house.  anything else I should plan for?