Thank you for the responses once again.
well what i am trying to do is basically find out is what would be the best method to analyze Lead water whether it is drinking or water found in the environment.
I am really interesting in developing a new method rather than rahashing ones that already exist. It doesn't have to be 100% precise just somewhat logical.
There are hundreds of reagents suitable for lead titration. Most of them where developed in 1910's - 1930's. Selection of the right heavily depends on particular application. You can use Sulfates, Chromates, Iodides, Sulfides and countless number of organic indicators. Some, most common, you can find in Analytical Chemistry handbooks. Generally speaking, selection of the reagent is part of development process. Nobody can tell you what to use without scientific review of what you are trying to analyse. And there is no such thing as "universal" reagent.
The second problem you will meet is selectivity. It is almost impossible to test lead with wet methods (classical methods) in presence of other heavy metals. You need to develop a method specific for your tested material: whatever is good for lead paint analysis, will not work for lead ore, or lead in blood.
The third problem: like I mentioned, chemistry lost interest in development of new titration methods and instruments, about 50-60 years ago. Titrators of all kind of designs, including automated, manual, computerized and other are available since 1930 (mechanical since 1950's). I am afraid, your instrument may not find it customer.
In few words, I would discourage you from investing your talents into invention of titration methods. This is in the past.
If you have interest in chemistry and are handy person, there is enough interest in truly valuable instruments and methods. I would order custom-made instruments from you myself (as long as they can deliver a result). Just let me know that this is something you want to try.