Your expectations for said build? 1MOA? Caliber? Definition of long range? Intended use?
Helps to scope the ask more. Have you looked at current options which are not custom? Custom work costs a lot if it is good. Factory options will likely be cheaper if money is an issue.
If not married to the 700 there are many more options out there. If the 700 is it Rem and many others make some great platforms, semi custom or fully custom but not done one off like a local maker would have to do for you.
Remington 700P or PSS in 300WM is worth a look if that fits your ask and won't break the bank. 308 if you don't need the WM or 5.56 if you will be shorter range.
You can also look at doing a remage barrel if you are looking at just rebarreling. Northland Shooter Supply sells Croterion barrels fairly inexpensively. If you want something nicer, look at patriot valley arms. It's not hard to swap if you get the right parts and are ok w a barrel nut.
Thanks gentlemen, I’m actually asking for a friend of mine who’s not a member here. But it sounds like caliber will be 7mm-08,Krieger 1/9 Barrel, lone peak or deviant action, in a McMillin or Boyd’s stock. Not a Rem 700 as I originally thought. He plans on buying all the parts and just needs someone that knows what their doing to assemble it properly.
There is a little bit more involved than just screwing it together. You need someone who really knows their stuff to get it right. Unfortunately, the smith I used passed away. RIP Sid Goodling. I do have a few rifles smithed by Randy Gregory and his work is impressive. He is not local though.