I have built all my LR rifles on military actions. Most have been P14/17 Enfields but a few have been mausers.
If you need to start from a stripped Military Mauser action, you will spend more money then buying off the rack. If you have one that is already sporterized with a stock and only needs a barrel, then sure why not. You should be able to find one already built for pretty cheap at a gunshow.
Just price out all the parts you need to build a Mauser action and make it look reasonable and you will have around $400 'spent'. Now you need a gunsmith to install all this stuff which will add another couple of bills to your cost. Resale value of half or less out of the box.
New Savages are so cheap and shoot so well, that it is impossible to build a rifle for less. The new Model 40 in 223 would serve you out to 500yds and is around $300. Single shot, push feed, lam varmint style stock, supposed to shoot well, and has a decent trigger. Add to that easy resale. WOW.
The only time working with a military action makes sense is if you want a 'classic' rifle or want to build something wacky that is not readily available.
Jerry