There is a fine line between going with a custom vs going with a Remington 700 and having it blueprinted properly. Here's the break down.
Remington 700 sps blued in a magnum caliber $550
Action Blueprint $150
Holland recoil lug $40 (factory one is junk)
Factory Trigger and bottom metal FREE comes with rifle (not the best but will do)
Total $740
Stiller Predator (Remington Clone) $825
Recoil Lug FREE comes with action
Timney Trigger $125
Bottom Metal $135 (Brownells ADL to BDL kit)
Total $1085
Now this is just if you go as basic as possible with no frills like adding a Jewel trigger (although they are the cats ***). A difference of $345 cheaper to go with using a factory Remington. Now if you upgraded to a Timney trigger with the Remington action the difference would come down to $220 cheaper to go with using a factory Remington. It is a bit cheaper to go with a Remington action and have it blueprinted, but the problem lies in how the blueprinting is done. There is such a thing as a actual trueing of an action compared to a half *** "this is what I call blueprinted" method. The ones that know how to actually blueprint an action are not afraid to explain how it's done, but the one's who just think they know will never speak up. A custom action should already have the the receiver face and internal locking lugs cut perpendicular to the bolt bore centerline and the threads should also be straight and in axial alignment with the bolt bore centerline. Hopefully this makes sense.