I for one only clean hoods because if we cleaned the equipment we could not get to the second job. At time we clean some equipment as a favor and it most always turns for the worst. If the equipment will not start you own the repair-just asking for problems. Some people do very well in cleaning equipment-we are just not set up for it.
Will, David is right, cleaning equipment is very difficult to schedule as you never know how long the job will take. When I clean equipment, and I don't like to, I tell the owner it is $60.00.00 an hour,+ chemical, I keep track of my own time, and I decide when the equipment is clean enough. I don't really like to clean equipment and it is not very profitatable, when you figure that you can make more cleaning hoods. If you decide to clean appliances, you will need a strong chemical you can brush on, leaving it undisturbed for 15 minutes to 3 hours. Scrape it off, re-apply. Do this untill you are satisfied with the cleanliness. You may need to move the appliance so you can reach all areas. Put down cardboard, newspaper to absorb the crud you scrape off. Use your 5-in-one paint scraper. On some heavy deposits you may need to use a hammer and the scraper. If you feel the need to use the PW, carry the appliance outside. Don't get water on elctrical connections, switches, relays or you may be in the appliance repair business. Don't use the PW on stoves with ovens or you will get the insulation wet. If you remove the insulation, you will change the allowable proximity of the stove to the wall and flammable surfaces. If you need to remove the grill, pull the knobs and the cover behind the knobs. Look under the grille for what looks to be wiring going under the grille. The wiring is really a capillary tube going to the thermostat. When moving the grille, be careful you don't pull the tubes apart or pinch them. Burners can be removed by lifting up the back and pulling them out. Do not change the setting of the round shutter at the front of the burner. The shutter is the air adjustment for the burner. If you soak any parts, make sure they are not aluminum or pot metal. After soaking burners be aware that they will not burn very well untill the water is burned out. Be gentle moving the fryer, some have a ceramic deflector that the flame impinges on. If the ceramic deflector breaks, the flame may be against the pot, leading to shortened oil life and early pot failure. Contact the local used equipment dealer and find out what chemical they use.
Sometimes I will loan the customer the tools to clean the appliances themselves, with the understanding that they need to stay out my way so I can get my job done.
If you decide to clean appliances, do not make any estimates as to the time, cost or quality of the job.