with debug mode active, I get an error... and finally, no realestate (sp?) option whatsoever...
Oh dear, where to begin? The litany of problems you describe suggests a number of things:
1) You likely do not have the latest updated awesome hacks. Make sure you have the latest hacks from Pescado's director's cut installed - DO NOT post an error message before you do this and re-test or you will be abused. If you install latest versions of hacks, you may find that many problems have been addressed already (i.e. the phone problems you describe). Go to the Armory and the Directory of All Hacks and get the latest director's cut from the BV directory.
2) The "some interactions are unavailable" problem suggests the work of the nonawesome. As this is the time of hack updating and redevelopment, you use any nonawesome and non-updated hacks at your own risk. Modders are understandably upset if you complain about problems with your game due to things they've already fixed, or because you're using something not made for the version you are playing. Remove nonawesome mods (especially Insim, if you have it) from your downloads folder and try the game again. Real estate and other options may magically reappear.
If, after these steps have been followed, you still have difficulties and error messages, then post an error message, AFTER you read the FAQ.