When you contact them, specify that you want to fast with Water only. They speak foreign languages. I don't think you'll find cheaper than them. Basically you can't expect a professional supervision for a couple of hundred of dollars.
http://emilova.eu/index.php/en/
Also specify that you only want basics: lying in bed, blood tests and supervision (no fruits as in modified fast).

Amazon has a film on the miracles of fasting called The Science of Fasting http://a.co/bVGYMMc as discovered accidentally by physicians in Russia and UCLA, independently. They have really cheap clinics, but since they show how to do it (clean spring water from glass containers, bathing in hot springs, clean lake or ocean water, sleeping, massage and stretching, I decided to just book a cheap AirBNB retreat without a kitchen and with a hot tub so I am trapped in a beautiful tree house cabin type surrounding without reminders of food.

Here's my plan: Book a cabin with no kitchen for few days at a natural hot springs retreat where there is no restaurant/store so I won't even think about food. I can soak out the toxins which makes fasting easier. Bring a kindle with binge classics like Anna Karenina or Ayn Rand audibles so time flies. Bring art supplies and paint. Bring crafts or scrap booking. Bring camera. Yoga mat. Free weights. Soft meditation music with earbuds (plainsong, medieval and Gregorian chants, haunting, healing American Indian flutes; bring a Tibetan bell bowl, neck roll pillow, thick socks, warm hat, broths in case I start to think I am starving.

Here's a choice: http://www.merceyhotsprings.com/things-to-bring/
https://www.google.com/search?newwindow=1&safe=active&rlz=1CAASUH_enUS745US745&q=california+natural+hot+springs&npsic=0&rflfq=1&rlha=0&rllag=38414866,-120766787,244907&tbm=lcl&ved=0ahUKEwjot-jb8qbYAhVpqlQKHbMaBPwQtgMIKw&tbs=lrf:!2m1!1e2!2m1!1e3!3sIAE,lf:1,lf_ui:1&rldoc=1#rlfi=hd:;si:15062457195052623173;mv:!1m3!1d2026513.0165416345!2d-119.79936714999997!3d37.93605225000001!3m2!1i860!2i483!4f13.1

The water found in natural hot springs contains a variety of different minerals, including calcium and sodium bicarbonate. When you bathe in a hot spring, your skin soaks in these minerals and your hydrostatic pressure rises. As this process continues, circulation and oxygen flow increases -- much like when you exercise. An oxygenated circulatory system is beneficial in keeping not only your heart, but your body's other vital organs and tissues, healthy and strong.

we could create a MeetUp.com group for this