@Tinker - I have gone through the TPA pdf Drs. Erik P.W.M.
In the case of estimation of Independent testing ( black box alone )to determine FP is tough na( To conduct a TPA, at the start up itself one needs access to a functional design, consisting of detailed process descriptions and a logical data model, preferably including a CRUD table. In addition, a
function point count made using the Nefpug ,Ifpug or IFPA technique is necessary.)?? but at the same time TPA is a good option and its accurate bcoz it includes all the important factors,that's why i asked the doubt.
I think in this case UCP analysis is a good option rt?