In the prospective of the GST , If unregistered supplier has made repair work at your housing society of Rs 50/- Lacs , then he liable to take GST registration and issue your Housing society a GST Tax invoice, because threshold limit to obtain GST registration for taxable service provider as per section 22 of the CGST act is 20 Lac , and you have paid him 50 Lac , which is more than 20 Lac . Not only this work , considering other work he may have crossed his Turnover, over and above 20 Lac . He can not keep himself as unregistered, ones he crossed threshold limit , he has to obtain GST registration.
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