I self warrant using Lawgistics books. I'm considering moving up to the administered package as they then do most of the legwork in terms of claims, you just pay.
Excellent, friendly and honest people to deal with I have nothing but praise for them. You get a claim, you can call them for legal advice to see if you're liable etc....
£6 a go for nice glossy warranty book - I give 3 months on all stock other than trade and upsell a 12 Month for £350. Every time I sell a warranty I put the £300 odd into a warranty account and then use that for any claims. I have had 1 gearbox ( £500 ) and 1 clutch ( £500 ) in the 10 months i've been doing this. so my view is i've saved £££ over paying £XX per warranty. Also whatever's left in the warranty pot at the end of the 12 months cover is profit. I like to think I buy relatively well, and that I prep my cars well enough so that they are decent quality and would last. However as we all know, stuff goes wrong. I find being the point of contact makes it easier, and I can authorise something in a flash. Also I find if you sort silly stuff out that most companies would decline, it helps build a better relationship and customer experience. I changed a fog lamp the other day for a lady, cost me £30 overall, she thinks i'm amazing and leaves me a 5 star review on autotrader, I'd have paid £30 for that alone!
I also couldn't do it to myself to have pictures of Quentin Wilson allover the place as per warrantywise POS - My garage also tells me they are terrible at claims handling.