My husband wants me to dress as a hooker, drive me into the town centre with no money and make me earn my taxi fare home?
While I think it's a great fantasy, I think the realization might require some planning, for safety sake. You and your husband should go to the area where the hookers hang out, and hire one of them just to chat with. Take her for a cup of coffee, and let her explain pricing, safety, avoiding cops, and if the neighborhood allows indies or is controlled by a pimp. If it is the later, ask to be introduced to him, and he can try you out, give you some pointers, and then put you to work properly, under his protection.
I would think he'd want her to work you for at least a weekend, and earn him a lot more than car fair, to earn your free training, and pay for the trouble of breaking you in and stabling you. If your husband tells him to work you hard and have you take on all comers for a a few days or maybe a week that should be more than sufficient to give you the full experience.
You'll have to follow the rules, of course, and he'd be free to turn you over his knee if you get lippy or lazy or try to hold out on him. The good news is your husband will be able to visit you whenever he wants, although he'll have to pay for you to drop to your knees for that back alley blowjob. Who knows, he might even bring a few friends along, maybe a neighbor or coworker who doesn't like you, or once made a pass at you, knowing that you won't be in any position to turn business away.