In a system of Riba, how do you protect yourself?

Re: In a system of Riba, how do you protect yourself?

One issue is that the world of interst today is so wide that you can probably find only a select few things to pick on in relation to what is mentioned in our classical literature. Secondly, Riba has been clearly defined in some cases when it comes to trade or exchange of things however from the perspective of sale at least I have not come across any convincing or at least material which gives me a convincing explanation of Riba.

For instance, someone said time based value of money is Riba. According to all classical jurisprudence and literature, this is not true. Time does have a portion of the price, this is the very basis of a Muraba transaction where the cash price is increased to a much higher value (almost all Islamic financial institutions do this based on how conventional banks calcualate interest rates in a mortgage) for deferred payment. What I cannot seem to dsitinguish despite reading up Mufti Taqi Usmani, Mahmoud A El-Gamal and other literature I have found on this is that what makes it Islamic when conpared to a fixed rate mortgage. Conceptually they are the same. All material I have researched, they just go one to say that Muraba is halal whereas the conventional mortage is interest based assuming as if one is going to refinance it. If I do not refinance it, to me it ends up being absolutely no different than the Islamic alternative being offered.

Can someone please elaborate on the fine point I am missing?