I have been using P3D v4 for about 2 weeks now and up until now I have been looking for Freeware scenery that was design for v4. But does older scenery made for v3 work in v4? What else would work in v4?

I know it can be tempting, but I'd hold off on installing any addon that isn't designed to be used in a non-32-bit environment. It could mess up a perfectly good installation.

Thanks. Unfortunately there is not much freeware for v4 and I don't have the money right now for payware.

Yeah, I haven't had much luck finding any freeware scenery either. But it's still early days. 

Depending which scenery type you are looking for...
As long as the scenery you are looking for does not contain "active elements" so to say, understand .dll, .gau; .exe files which until now were coded in 32bits mode, and that there is no FS9 (port-over, original modelled element, etc...), you can install the scenery and check how it works.

P3Dv4 is 64bits code only, and accepts FSX native stuff other than the above mentionned active elements.
For instance, if your addon uses for instance dsd_sound gauge programmed by Doug Dawson, you will need to go to his site or other usual site to collect the latest version, coded in x64 mode.
With elements of FS9 origin, you will have display or rendition problems, not to say sim crashes.

I have very few addon scenery on my P3Dv4.1, but am running without problems the FSX Barra airport, or various RAF air bases (FSX versions) as released by Terry Boissel, as well as the necessary objects libraries (also FSX versions).

Blue skies