Getting a new car soon and often give a lift to friend wearing work clothes. Rather than fit an ugly seat cover on the passenger side are there any 'treatments' that can be sprayed on the seat and that will protect the fabric from getting dirty, or that will make a simple vacuum all that is need to return them to 'as new'. 

Personally speaking, I've treated my (part alcantara) seats with GTechniq I1, and this protects them from liquids but also makes them repel the dirt better IMO.

 

Kids had got footprints over them in the back and it simply took a quick vacuum to bring them out.

I feel like I'm always recommending Gtechniq here, but another vote L1. Great product, but in no ways unique as a tier proofing product.

Sounds good but I am concerned about the smell/fumes as my wife has allergy asthma - any idea how long it really takes to disapear completely.

Seat covers. Plain and simple. Quick to fit, easy to clean and keep the seats like new

Day

If I was being given a regular lift in a new car I'd be mortified at the thought of wearing work wear on fresh upholstery and would either supply my own seat protector, or take a change of clothing with me. The latter option could be the preferred option for your friend.

Another vote for gtechniq

Sounds good but I am concerned about the smell/fumes as my wife has allergy asthma - any idea how long it really takes to disapear completely.

Smell is very potent on application, but soon dissipates and there is no trace when dry.

Cheers

Steve