Would like your opinion on wedding dress alteration dilemma. . .?

if i were you, i'd go back to the store and "try on the dress again" and while you have the dress on, i would remind her that she told you x amount of dollars. if she says, "no blah blah blah".. i would say.. "i am giving you $140 and THATS IT!" and put $140 on the table and walk out the store with the dress on. what can she do? she cant touch you. she cant rip the dress off of you cause then if you call the cops, shes at fault. if she calls the cops and says that you stole the dress, thats bs because the dress was yours and you gave her $140 for the little alterations made! she cant take yout to court cause she has no contract stating that she said x amount of dollars and you can say it was word of mouth that she said x amount and then tried to triple the price. either way, you spend what you were willing to spend and you get ur dress. lol