Call REAL professionals for exterior services
While Matt Yorke is a nice guy, our impression is he relies on his dad to guide him. His dad is nice too, but I don't think he knows as much as he professes.
Due to Ravenshead Exterior Cleaning not showing up, I contacted Yorke Exterior Services and Matt was responsive and available to pressure wash, re-mortar our tiles, and clean the gutters and soffits. A bit pricey, but we wanted it done. He used Google Lens to ascertain the type of tile..which is slate. He quoted me for the job and was set to go April 29th and said it would take 2 days. He and his dad arrived and finished in one day and offered to seal the slate for an addtional 100 pounds...however..long story short...they did not seal the slate properly making mottled puddles that dried on them everywhere....HOWEVER, they did agree to return and remove the sealant. But they scratched all the tiles with a brushed cleaning machine..(slate scratches). We complained about it and therir response was they were already scratched, but I had before and after videos so this is untrue.
We provided the videos he requested and he said that the machine would not damage the tiles...it isnt a brush machine..yet I have video of his father using a "brushed" machine. You'd have to replace all the slate.
Matt was supposed to arrive the following week, May 9th, to replace the mortar that ended up being removed by removing the sealant. He needed additional mortar that I had to order. He sent me a WhatsApp message the night before saying he wasn't returning and suggested I find another company to follow up. He was willing to return 200 pounds of the 900. I asked for 300. I got 200 which is better than nothing .
Bottom line, I ended up re-mortaring the garden myself. Still have scratched slate, but it is what it is.
I suggest making sure the company you hire really knows what they are doing.