If you are more excited than he is, back away and get his plan. Its his place, and although its nice of you to offer to lend a hand, ultimately whatever is wrong will end up being your fault if you take it away from him. Don't own the mess if it goes sideways.
Having said that, and only skimmed through the thread, I would call an aggregate supplier and ask for "A-gravel" sometimes called roadbed. Lay it in to your 3" depth, sloped at least at 2% in the best direction for drainage. You need to get the slope going away from the building and out from the corners of the patio or you will end up with ponding/puddles in the corners. Get a good compactor or plate tamper and pack it good and flat.
Once you are satisfied with the slopes for drainage, come in with rock dust or sand and stringlines and lay out your bed. Now you can put in pavers or interlock over the sand.
With the pavers in place, follow up with polymeric sand. This is sand with s cement-like compound that you sweep into the spaces between pavers. The sand will lock everything in place, then harden to prevent weeds growing in the cracks.
For cutting/breaking slabs, there are a few techniques you can use. A cold chisel and a hammer is both cool and gives you a feeling of brute power. A second method is to get the cheapest skilsaw available (seriously - aim for $20) and a masonary blade. Score the paver while dribbling water along the cutline, then tap it with a hammer to get it to snap along the cutline. Test the GFCI's before doing this as water and power tools can be a bad combo.
Our last hardscape project was a
retaining wall and pool deck that near killed me. I built the wall in spurts of 2 hours after work, then brought in a pro for teh pool deck once I had burnt up too much of the summer.