If you developed your ASP.NET application following best architectural techniques for Scalability, Loose coupling i.e. Dependency Injection a.k.a Inversion Of Control Containers (IoC), Aspect Oriented Programming (AOP) then you need Full trust permission because all these techniques rely on REFLECTION which will not work in Medium trust.
The default permission in IIS is Full Trust hence we will not see any problem during development but while going to deployment in a shared web hosting i.e. GoDaddy we will see all sorts of ASP.Net permission errors because most of the shared web hosting company will not provide Full Trust and also deactivate overriding Trust’s through web.config file for security constraints.
So please aware and identify the right web hosting company well in advance in case if you rely on best in class architectural techniques. This was my experience………………………….