The paper introduces some challenges of the fast growing mortgage market in Poland, being also the next step of research presented in previous publications, showing the complete process of building and verifying three submodels for the internet mortgage market. The sub-models are described for three market situations, i.e. stable market, crisis, and boom, then the variables within the models are analyzed statistically (e.g. correlation level) and finally the models are verified. The paper presents the process of verification of submodel nr 3 (fast growing market) as an example of the verification process that was applied. The paper concludes with directions for further research in this area leading to the ultimate application of the proposed model in a real life prognosis process.