Does the vehicle have over 50 k miles? If not it should be covered by the 5year-50,000 mile emissions warrantee since any evaporative emissions problem would potentially involve unburned hydrocarbons into the atmosphere.
Most CEL problems that are not maintenance related should be covered. At least they were when I was in the business.
Since you don't have a service manual to use for guidance you can go to Auto Zone and give them the code numbers or have them scan it and they can print you out a list of things to check pertaining to the codes you have.
Emission Warenty's are Federally regulated. Some things are covered for up to 8/80.000. It depends on what part/problem is. If you have the original owners manual, there will be a seperate warrenty booklet with it that will explain/break it down. Or call/go to the dealer. So it might still be covered on waranty, depending what the problem is.
if i had to make a guess w/o actually diagnosing the concern, i would stick a purge valve in it. this may or may not be the cause of all the codes
if you have a "evap purge flow fault" its the most likely thing to cause it. on any vehicle i've seen this on the dtc for "evap purge flow fault" is set when the evap system senses vacuum at a time when there should not be vacuum. the reason the system has vacuum is caused by the purge valve not sealing allowing the vacuum. or just think of it as evap purge flow fault = evap purge valve flow when not desired.
other options to set that code , in order of likelyhood, would be faulty/incorrect ecm programming(newer vehicles), faulty pressure sensor that shows vacuum when it is not present, or faulty ecm
and of course, actually having it diagnosed would be a more surefire way of fixing right the first time
I agree with double checking the warranty coverage, why pay for something you don't have to?
If it isn't covered I'd check the evaporative canister first. On the xB the evaporative canister is under the cargo floor behind the rear axle. It is the black box you see in the middle of this picture:
Since it is exposed, it may have been hit by a kicked up rock or something and damaged something or knocked a connector loose.