Write some Software

I am a publisher and takes offers from [login to view URL] are mainly two softwares that I deal with one is AFFISE and the other one is CPAPI by AFFISE. Advertisers use different softwares like CAKE,HASOFFERS,FUSECLICK etc. I use AFFISE. To sync offers from advertisers platform to my platform he gives me API key so that I can access the offers on his platform.I put that key in CPAPI and sync offers from CPAPI to my [login to view URL] I need a platfrom instead of CPAPI because it has its limitations so can you tell how much time is needed to build a mediator platform Like CPAPI and the cost involved in it?