The CTAPI Service Contract Entry web service is modeled after the Solomon Screen: SN00100
The recommended and quickest way to implement is to use the ctDynamicsSL.fieldService.serviceContracts.maintenance.serviceContractEntry.screen object which contains all necessary objects to create SMContract, SMContractBill and SMContractRev entries.

All necessary pv lookups are available in the service.
Examples:
public ctDynamicsSL.SegDef[] getSubAccountsByID(String ID)
public ctDynamicsSL.smEscHeader[] getEscalationIDsByEscalationCode(String escalationCode)
public ctDynamicsSL.smBranch[] getBranchesByBranchID(String branchID)
public ctDynamicsSL.smAgreement[] getContractTypesByAgreementTypeID(String agreementTypeID)
and more...

Contact Catalina for sample code for calling this webservice

Programmers Reference for: ctDynamicsSL.fieldService.serviceContracts.maintenance.serviceContractEntry