>>528250742
The TL;DR is that there are 3 steps to the process in my eyes and people over complicate it usually with the steps inbetween as they are looking for something specific.

>Step 1, base
Find a base with good mods on 1 side
or essence/fossil slam one yourself
or harvest reforge until you get something you want
or recombinator for 3x T1 prefix weapons
bonus: get a fractured mod on the other side (like spell suppression) beforehand

>Step 2, reroll
Look for mods in the mod pool which you want to add ontop of it
In this case the PDR roll is essentially free on armour bases because
This is where craftofexile comes in; you check it for options and more importantly the tags on those options.
PDR is a physical tag and the only one
Harvest has "reforge with physical tag"

Meaning we can get a good triple prefix mod chestpiece + pdr for the cost of the base + "cannot be changed" metacraft
Some other good rolls are Chaos Res

>Step 3, clean up
Up til now it's been cheap / consistent, but this is where you pray.
Since it's for mid-level items, at this point we have 4 mods of T1-2 that we're happy with, and we're looking for just a really solid rare we could potentially sell later
For jewelry a fun thing I like to do is check the influence exalted orb mods and just ex slam them with something cool rather then generic.
Getting a styg vise with life + 3x good res is not that expensive, and you can hunter exalted slam it and hope it rolls chaos % or max life %.