1. I have to say, most of my time wasters have never done that, just endlessly parade about on when they'll book while asking for freebies.
2. I've done outcall to homes quite a few times. I'd say only if you get the postcode/road in advance so you can scope it out.
3. As a scientist, OWO is insanely low risk for STIs. Sure you can get herpes, but 70% of the population has oral herpes (had a cold sore? You've got herpes), most of us get it by 5 years old orally. Then you can't ever get it again. HPV, actually leads to better outcomes of oral cancers. Chlamydia and gonorrhea, very rare. Syphilis, you should spot the rash/sore easy, contact with that transfers it.
That said, entirely your choice the risk you're willing to take. I opt for OWO because I've nearly choked on a condom doing deepthroat more than once.
4) never ever, ever answer the phone when with a client. At least in my opinion I never do, it just seems extremely distasteful.
As for the rest, I offer a shower and drink on arrival, and as per my profile offer multiple orgasms (but I pretty much only do long bookings, so it is rather expected).