Hello,
Few notes regarding my proposal, if any additional questions please feel free to ask:
-I code with care and provide quality results especially for applications targeting the .NET Framework(if needed I can show over a short remote session what I mean by that, more relevant than that I am on 1-2% top percentile on exam result here for C#), so the proposed fee(~400 USD on my side without taxes) would be the minimum to start from, of course for a 100% clear deal and final price, the complete needs included for the traffic part should be discussed.
-Visual Studio edition matters less(even if not having license for newer, you can get a free community edition of 2013 or 2015 RC as good as a Pro version). What matters is target .NET framework, that depending on deployment scenarios.
-Separate assembly strongly recommended, if not making your software modular is a nightmare to maintain it.
-I assume that the project would imply using a free or paid library meeting your licensing requirements for offline OSM handling, not reinventing wheel?
-My preferred language is C# not VB.NET but they compile to same IL so you could call it from your code same as a VB made assembly, are tools to convert from one to other, so which using would matter less for final result. I am most productive with the former
-As mentioned, traffic part of task is important to be detailed too(I assume that some Web Services to be consumed).
Would be more to say, but characters number is limited.