I use albuterol sulfate ProAir rescue inhalers for my asthma. Can I use salamol cfc free inhalers in replacement of this? (it's more affordable)

Yes. Yes, they are essentially the same medications. They fall in the category of SABA, short acting beta agonists. As always, with asthma, try to use these as little as possible to prevent your lungs from becoming 'sensitive'.