Choosing a studio is of course exceptionally important to the eventual success of your shoot. It is vital that whenever possible you should arrange to see the studio prior to booking. Always call the studio before your visit to check you will have access to view the studio(s).
You can tell a lot about a studio hire company by the way you are greeted and treated. Were you offered refreshment when you arrived? Does the studio have printed material and a printed rate card? Does it seems to be adequately staffed? Were the phones ringing? Did it seem like a busy studio? Do you recognise any names of photographers who currently shoot at the studios? Get into the studio as soon as possible after your arrival. There is little point in wasting time chatting with the studio manager or staff about your requirements if the studio turns out to be unsuitable.
The best time to actually see the studio will depend on whether you will be using the natural daylight afforded by the studio. It will probably be better if your visit is timed for when you expect to be shooting. This way you get to view the studio at a time when you will probably be shooting plus the studio has by now done their job in looking after the clients shooting on the day and can give you their undivided attention. Ask the studio staff about the natural light during the day. Does the studio have air conditioning? If the studio has lots of natural light it will probably get pretty hot, ask how they cope with this.
If daylight is not a consideration for your upcoming shoot then you have a wider latitude timing wise, to view. Try to get in at the start of the day. At least you will see how well the studio staff are organised plus you are less likely to be obstructed by a closed set.
So you have registered your first impressions of the studio (and staff) and hopefully it is looking good. The next step is to explore the resources the studio has to offer and the prices. Whether you are the one picking up the bill or your client, you will want to avoid any unpleasant surprises. After all, if you have decided on this studio and your client was used to shooting elsewhere, you will want to be sure there is no cause for your client to feel you made the wrong choice. Find out what is included in the studio price and what isn’t.
Regarding standard studio items and items you will need to have brought in. The question to ask the studio is what equipment do they have on the premises and which hire company do they use for hire equipment. Studios dislike hiring in equipment for a shoot which they already own. From their point of view this is lost income. However, studio hire companies with multiple studio facilities will hire their in house equipment on a fist come first serve. So if you reserve equipment prior to your shoot and then decide you no longer need it on the day you may well find you are still charged a cancellation fee for the equipment they may well have had to hire in for another shoot since you had reserved their in-house items.