If you're getting a new rig built, then ask how much cheaper a 3070 LHR would be instead of a 3070. It should get a discount,
So you'll get same performance card and cheaper. The disadvantage is that the card won't be able to mine. But that's why the card could not have been 2nd hand from a miner either.
When you receive the rig then check the Device Manager and make sure it is an LHR card listed.