https://api-prod.corelogic.com/trestle/odata/Property?$filter=toupper(StreetName) eq 'MAIN'&$top=5&$select=ListingKey,BedroomsTotal,PropertyType,StreetName,StreetNumber,City,ModificationTimestamp,OriginatingSystemName,OriginatingSystemSubName,Appliances,ListingContractDate,AssociationFeeFrequency
Convert a string to upper case (toupper). Lower case would use the function tolower().