TS I suggest you take the lens to the service centre to get it checked and confirmed that it is fungus first before deciding where to send for cleaning.
There was once I have a cheap lens which I thought got fungus, and I brought it down to Peninsula shop to assess cleaning cost. The lens cost less than $300 but the shop quoted me $90. Was told its initial stage of fungus growth. They say it's because it got dunno what electronic thing at the base and they need to open it up, and takes lots of work. Recommend me to go to service centre instead.
When I went to the service centre, they took it in to assess. After half an hour, the lens came back, and I was told that there was no fungus in my lens at all, just dust. When I asked why the spot looks like a bit furry (root-like), they mentioned that there are many different types of dust in the air, and what I have is just dust and not fungus. I double confirmed at least 3 times before I am convinced. I left the service centre without having to pay a single cent, and the technician actually did a minor cleaning on my lens too.
After that incident, I tell myself always to go to service centre if I am not sure. Wonder why the shop tells me it is fungus........
Anyway, you only pay if they service, they don't charge to assess