I want to set up new prices for my rig and I get this "Invalid rental plan. Maximum rateplan variance exceeded."

That's designed to stop you inputting an obviously incorrect number ie with a decimal place out (but not sure what percentage it uses)
Check that isn't what's happening. If that fails delete all your current prices and start again with your new ones.
I think it's set to 5X.
The issue as Tigggger pointed out was that there was decimal errors going into rentplans. The variance check was put in so that when you are quickly making a bunch of rentplans one of them isn't .001 and the next .01 since it caused the providers some headache with refunds and even a 646 hour extension on a lease
