Wrong information to costumers

I saw morclick advert on Facebook then i request a call,then saleslady call me the next day I ask her to give me more information regarding they product,she told me what they need to apply,then after I ask her if there was any upfront payment or anything she no I ask her again if there is installation fee she said no ,then I told her we can proceed with application if the is no installation fee I even explain to her I declined companies like rural saterlite internet because of this installation fee I can't afford it ,but to my surprise two days after installing saterlite I got email that contains invoice and statement a call them and ask about invoice that's when I was told about installation fee and transport my question is how on earth will afford to pay that amount from the money I earn , please help me with this problem.