& dont forget the other important thing like your reputation & PLI if things do go wrong its your details on the tag.
A while back i was approached by a old friend with his own company who had done a job over & around a church which tbh really should av been desighned for loadings on the roof etc- he offered me £100 cash to give it the once over & sighn it off....after inspecting it the snag list would have cost more to put right as it was horrendous.i gave him the snag list but no sighn off & said once he'd done it i"d recheck & sighn it off. In the insuing weeks i heard through the grapevine that it"d had aslip & small collapse damaging a large portion of the roof ...hse got involved,the insurance company wouldnt pay out cos unqualified labour & no desighn. I'm just glad i didnt sighn it off but some would av lked at it as easy cash & done it anyway