Our petshop gets them for about 4-7$ depending on who bred them and all that. We sell juviniles for 25$ but those are generaly handled when theyre young so overall come out nicer. So the price they're asking is just fine you probably wont find one cheaper than that unless its sick or something. If they tell you its tame its PROBABLY not true because most pet shops dont sell them tame. If its sitting there and doesnt respond quickly when you get near it with your hand its probably sick. Check to see that the ribs arnt showing and theres fat at the base of the tail and on its thighs. Tokays arnt very hard to keep so I think you would do just fine with them if you kept pictuses. Just some basics:
Tall tank, lots of hiding spots (theyre nocturnal so they hide during the day), preferably 20 gallons
Temperature: 80-90 day (85 best), 70-80 night (78 best)
Humidity: 40-80%, 65-75 best and causes least shedding problems. Cork bark keeps humidity up.
Food: Crickets, wax worms (treat), meal worms, silkworms, hornworms (store bought only), baby mice (pinkies), and occasional fruits and baby food (mine likes banana sometimes).
Anyway, dont make plans to tame an adult if thats your aim. Generally they wont tame down when theyre that old but you can always try. Just make sure not to stress them out because they do drop their tails which never grow as good looking as they did before. Good luck.