I am aiming towards starting a career in investment banking in about 3 months. Although I understand financial and managerial accounting, I don’t know anything about creating financial models for businesses or real estate.
I would suggest starting with Learn Financial Modeling | ASimpleModel: it is a free resource that provides video-driven material with notes and templates available for download.
From there I would move on to http://www.Macabacus.com: the material on this site is more advanced, and provides some instruction as well.
If you make it through the instructional material on both, try downloading SEC filings and building your own model. The process will expose what you need to revisit.
All the while, use sites like Investopedia – Educating the world about finance to stay on top of new vocabulary.
Also, if you are settled on investment banking I would advise reading Investment Banking: Valuation, Leveraged Buyouts, and Mergers & Acquisitions. In addition to covering the various aspects of valuation and modeling, the text also covers the process of moving through a transaction and describes the documents required.
All of the content mentioned above is free with the exception of the book, which costs ~$50.
As for my background, I started in banking (~3.5 years) and have been in private equity for the last 5+ years (note: now 6+ years). I built ASimpleModel to show that while some models can be complex, most are simple – they all have varying degrees of detail, but the mechanics are generally the same for standard models (integrated, DCF, LBO). In any interview process the model required is also likely to be pretty basic.
I pasted a few additional resources below.
Learn Financial Modeling | ASimpleModel
NYU Stern Prof. Aswath Damodaran
Investment Banking: Valuation, Leveraged Buyouts, and Mergers & Acquisitions
Breaking Into Wall Street
Training the Street
Wall Street Prep