Can I refuse to complete a purchase if the survey reveals problems?

Whether you can validly withdraw without facing the standard penalties for failing to complete depends entirely on the specific wording of the survey condition included in your konvenju, since if your agreement genuinely includes a properly drafted condition making completion contingent on a satisfactory survey, and the survey results you've received genuinely and reasonably fail to meet whatever standard was specified in that condition, you should have a legitimate contractual basis to withdraw without triggering the usual deposit forfeiture or damages consequences that would otherwise apply to simply changing your mind. The critical factor is how precisely and clearly the survey condition was actually drafted in your specific konvenju, since a vaguely worded condition, or one that doesn't clearly define what would constitute an unsatisfactory result, could create genuine disagreement with the seller about whether your specific survey findings actually trigger your right to withdraw under that clause. Given the genuine financial stakes involved and the importance of correctly interpreting your specific contractual condition against your actual survey findings, it would be important to have a lawyer promptly review both your konvenju's exact wording and the survey report itself, to properly assess whether you have a valid basis to withdraw and to help you communicate this properly and formally to the seller.