Where to get free standing gas fire from Britain serviced?

I have a free standing gas fire from Britain that requires servicing, can anybody assist and what is the cost please.

Ambifuego at Los Montesinos service fitted gas fires - though there is a waiting list at the moment and the cost is 80 euros. I asked about having free standing heaters serviced and the lady said, they are 'very low technology' and whatever you do, they smell. So no, they won't touch them. She also pointed out that you have to renew your gas certificate every five years, otherwise your house insurance is invalid in case of fire. And it's unwise to have anyone other than a gas service person service anything.
I also have 2 free standing heaters, both of which are very efficient but give me a headache in a very short time as they need a lot of ventilation around them - which in turn, cools the room. You can't win really!

Cheers Suzanne

They also generate water so you can get a lot of damp and you usually find the widows start going mouldy where the water condenses. not the best heating!