Whenever you’re looking for a hosting provider that will facilitate your test and development operations, look for plans with the ability to query multiple databases simultaneously, so that you can work on a number of projects at the same time.
What else to look into
First, talk to human specialists with the customer support in that live chat. You already know that you are in for lots of playing with different technologies and solutions, so you need to have some tech people to back you up in a tough spot.
Second, go for a plan that enables you to hook up a bunch of addon domains. Some hosts will get you up to 50 sites for the cost of the same package! This way, you’ll be able to work on all your projects at the same web host, not being concerned that you might need to make space for new ones coming in.
Third, even though you are just developing the site and it’s not live yet, you should definitely go for a VPS plan, so that your customer’s people see the site whoosh around. There’s nothing worse than a stunning site in development freezing on you all over the place.