You can't afford to rent and cart around a port-a-potty, so the only other
choice is to point your cast and crew to the nearest ally or street corner.
So the fastfood restroom seems like a fine idea.

What would YOU want if you were working on crew? But yourself in their
place. If you were thirsty and on an outdoor location would you want to
wait for a firm schedule or would prefer a bottle of water provided by the
producer?

Ask the women in your cast. They will know far better than anyone what
they need. Quite frankly, women aren't that different from men is what
makes them comfortable so I suspect everything you provide for the men
will apply for the women.

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The aim of an argument or discussion should not be victory, but progress.
Joseph Joubert, essayist (1754-1824)

Bathrooms: Have you actually researched the cost? Try here to start: http://www.mesawasteservices.com/faq.php IF the cost is still prohibitive, talk to someone there and simply ask them for a deal or donation in exchange for a credit or some kind of on-screen mention with a background sign. Product placement and bartering takes place all the time on every budget level and in many departments.

Another option that would be even more useful, particularly if you're shooting A LOT of exterior locations with a lot of company moves throughout the day(s), is a motor-home of some kind that has a bathroom. This provides A) a production office space, B) dressing room space, and C) a bathroom that travels with you.

This is no small issue. It's likely impossible that you'll ALWAYS be shooting within walking distance of a business that will allow you to just use their facilities without purchasing their products, so to rely on that idea may not be the best thing for your production.

You're likely willing to spend money on a camera, lights, sound, wardrobe, props, makeup, set dressing, editing supplies, food... consider "dressing rooms/bathrooms" as another necessity that you SHOULD plan on devoting money for.

Food: I couldn't help but notice that you only mentioned the cast in your question. Your CREW will likely be working harder and continually throughout the long day during setups and the takes. Why exclude them from having access to water and energy-sustaining snacks? And yes, you absolutely should have those things available, particularly if your cast and crew are volunteers.

If you have a motor-home, you could keep a supply of those things cold inside, but you should also have an easy-up near the set with a folding table that has the packaged snacks and fruit. A cooler with water and/or other cold drinks should be next to that table. Someone with your crew should be dedicated to setting that all up and keeping it all fresh throughout the day.

This may seem like an extraneous expense, but your cast and crew WILL perform better throughout the day when they perceive that you have their best interest in mind. It's the little things. 🙂

Also, have a variety of snacks and drinks as some people may have special dietary needs or allergies that you have to be aware of.

Women: Well, having an indoor place (like the motorhome) for dressing, makeup, and a bathroom will go VERY far with women.

I don't have stock in the motorhome industry, so I'm not pushing it for any reason beyond experience with shooting extensively outdoors in multiple locations. Again, you provide equipment that you need ALL the time for your production (like camera, lighting, sound) and you absolutely also have to provide proper equipment per the locations you are at. A film production is like a temporary temporary factory and like any factory/business, you have to provide the same infrastructure for your "employees" to work in wherever you go. Sometimes your "infrastructure" has to be portable while other times, it can be less so. You're likely not renting a Panaflex package so you don't have to go rent an expensive motorhome like a Provost either. Again, call around local rental businesses to see if they can offer you a deal. OR, ask ALL of your friends and relatives to find out if one of them HAS one already that they'd be willing to donate for you to use. You'd be amazed at how nice people can be, particularly when it comes to helping a movie get made. And, you could offer to put them in the background as extras. There's nothing like being on-screen that makes people smile and offer to help. 🙂

Point is, if you should have and/or need something to get your movie done, don't give up on it just because your own bank account can't afford it. Ask for favors or donations or deals. And once you get one local business or friend to offer their product or service, you use that as leverage to approach others (ie, "Mr. Smith is graciously donating his motorhome to us and he'll be in scene 3 as an extra! Could you help us out too?")

Brian Dzyak
Cameraman/Author
IATSE Local 600, SOC
http://www.whatireallywanttodo.com
http://www.realfilmcareer.com

Bottles of water. Small sized bottles of water. The large ones might seem a better deal but at the end of the day you'll find dozens of half filled bottles as people lose track of which was there's and grab a fresh cold one. When your paying those wasted half bottles are extra annoying.