My initial recommendation to you is to look to buy the best grills that you can. In catering, high-quality grills can differentiate between a consistent finish and a ‘good and bad days’ experience. If you want to build a strong reputation, I recommend that you focus as much as possible on choosing the best commercial catering supplies you can find.
Grills are easily the most important investment your company will make. A good, high-quality grill can distinguish between success and failure in catering. Thankfully, many places exist online in the UK where you can buy quality grills; one example is RJ Enterprises (https://www.rjenterprises.co/commercial-catering-supplies/). They sell some top-quality equipment for fair prices, and it is from top-quality brands like Ernst Neumarker. Other investments in catering include waffle makers and crepe plates, especially in cafes.