Are they registered painters
It is very important to make sure they are registered with the Government of Western Australia – Department of Mines, Industry Regulation and Safety. https://www.commerce.wa.gov.au/building-and-energy/find-registered-painter
In case there is a warranty issue or a dispute, a registered painter is obliged to rectify the workmanship. Delicate Painting is a registered painting service provider and proudly has got zero workmanship warranty claims.
Check the online reviews
Reviews are a great measurement tool to assess whether the business is operating in a professional manner and what quality / workmanship can be expected from the company. Not always are the reviews adequate, but it will give you a general opinion about the business. Painters Perth who have been on the market at least a few years have all got reviews.