There are people who like to wash and clean their Salah mat by themselves and then there will be people who like to have cleaned mats for praying but they do not have time to clean that and sometimes they will get annoyed when they see some stains or dirt on their mat especially on their travel prayer mat because they have to use that in so many places and during travelling it will get dust and sometimes stains on them. You have to get a properly cleaned mat for praying otherwise your prayer will not be approved so if you do not have time or expertise to wash them then you have to send them to the professionals and get them washed. You have to see the following characteristics in the cleaner:
They have to be the expert in that which means they should know that how to wash each kind of material when you send your prayer mat to them. You need to be careful in handing over your mats to them and it is better that you send only one mat at first and see how well they wash them and in what condition they will send you back. If you feel satisfied then you can send more prayer mats to them as well.
You need to see that how much time they will take in order to return prayer mats back to you. You have to ask that in advance. When you wash that in your house then it will take about few hours to wash and then about 2 days to dry them completely so you have to give them a margin of atleast 3 days although they have advanced machinery and they should wash that earlier than that but you should give them enough time so they can work on your mat properly as they also have other clients and they need to wash their mats too.
Machinery and washing agent:
You need to check their machinery that it has to be the best and according to the washing of prayer mats because some of them are very delicate and these machines should handle the delicacy with care. Also you have to see the washing agent which they are using. They know they have to use mild one but you can ask.