a load test indicates if the voltage your meter is reading is really backed up by the amps the battery is rated at {"CCA"], that is, when you call for full power can the battery deliver it - many places that sell batteries test them for free, NAPA here will do it ... even if it costs a few bucks it might save you throwing money at things until you realize the battery is the remaining problem
a quick search of your area finds a dozen or more shops that offer electrical repairs, consult one of them to find out just what the problem is
Bill
