Harry, YOUR RIGHT ON THE MONEY and it shows you did your homework congratulations.
OK lets address the piping.
We both know Plastic is JUNK We agree BUT I see nothing wrong with using it for venting BUT the savings over no hub cast Iron is minimal at best so I would stick with the Quality of cast Iron.
Copper for drainage is normally type DWV PAPER THIN and I wouldn’t use it even for a vent pipe.
For water lines if conditions permit copper Type “L” above ground and “K” below ground.
I never use “M” tubing even for heating applications as like DWV its THIN wall doesn’t impress me.
Now under ground waste or soil I like Extra Heavy Cast Iron soil pipe MINIMUM of 2″ diameter with caulked lead joints, BUT NO HUB if properly installed with a clean fill and proper bed will last years.
The problem with bell and spigotH above ground is the bell causes much more loss in space do to the hub and you have to allow for a wider pipe chase.
As long as you make sure that you specify “Domestic” Pipe and fittings I am sure NO HUB cast Iron will give you years of trouble free service.
Now as far a drainage is concerned PUT IT IN WRITING that all 90 degree changes of direction will be either LONG SWEEPS or short sweeps if a longer radius fitting cant be used.
1/4 Bends are ONLY to be used on vent piping BUT if (2)45 Degree fittings can be use instead of 1 1/4 bend go fo it.
IM sorry I should have mentioned the following.
In drainage instead of saying
90 Degree Ell we say 1/4 bend or sweep or long sweep
1/4 = 90 degrees 1/8 bend = 45 1/16 bend = 221/2 etc.
Now even the best piping systems can fail do to LOUSY installation like morons hackers, low life’s who would use “band iron” instead of proper supports like clevis hangers and on the vertical riser clamps (pipe rests) SAME material as piping copper on copper and heavy steel on Cast Iron.
The good thing about using either no hub or mission couplings (NEVER FERNCO) is you have accessibility to the piping if you ever need to add more fixtures Or if you need to snake/water jet these lines.
Having the proper supports is important BUT so is the spacing local codes will give you the minimum spacing and proper pitch.
On any hot water riser it is always advisable to use a four fitting swing for expansion and contraction when coming off a riser and a return circulation line is a MUST.
Now what good is using quality domestic materials with “Rated” Valves if the Master plumber sends over an apprentice to do ANYTHING but carry materials and clean up and dig holes or act as a fire watch when the REAL MECHANIC either solders or brazes or pours a joint.
I think you should ask to see the license holder and demand his CERTIFICATE of insurance (I carry 10 million unless IM doing a commercial, institutional or industrial job then I get a rider for 25 million) Hey I like being protected and THANKFULLY I NEVER HAD A CLAIM against me.
If you have any questions please feel free to E mail me as you sir are honestly one of the most knowledgeable home owners that I have ever met on here.
You should be congratulated for honestly doing your homework. I am sure your investment will last a long, long time with trouble free service.