When we were discussing clauses to put in a sales and purchase agreement to buy an investment property we struggled to find one that fitted all our requirements.  Below is one that we believe covers the following; building inspection, drug testing -  P labs, water tightness, plumbing and electrical.

This agreement is, in all respects, conditional upon the purchaser being satisfied that the property is suitable for the purchaser’s requirements following the purchaser carrying out a due diligence verification of the property, including by way of example and without limitation...

1.The value and condition of the property including compliance with building and local authority regulations.

2.The terms of all encumbrances, rights and interests registered against or in respect of the title.

3.The overall financial suitability of the purchaser’s proposed purchase of the property.

The date for fulfillment of this due diligence condition is that date being (__) working days (we recommend 10 working days) after the date of this agreement. The parties acknowledge that this due diligence condition is inserted for the sole benefit of the purchaser and may at any time prior to this agreement being voided be waived by the purchaser giving written notice of waiver to the vendor.