[AussieinNC]

When I built my "shed" I knew beforehand exactly where my two post would be located....

I poured extra concrete depth in a 4 feet by 4 feet area centered under each post location, used rebar in the pour and used fiber in the 4500 psi mix. I used 12" long 3/4" expansion anchors instead of the supplied 6" anchors....but that was my preference.

The shed has 13 foot full clearance so the "usual" height two post (146" to 148")...

Also consider the power service supply for the hoist...power requirements are listed in the specifications pages of the hoist install manual...I placed my service supply on a dedicated 220v 30 amp circuit.

I have seen some owners use a combination of supply sources then be driven crazy trying to diagnose why their hoist loses power etc.

I decided not to use embedded J bars as its almost impossible to keep them correctly aligned during a pour process.

Hope this helps...