Venere.com is a very reputable company. I used them to book my hotel in Florence last year and got a very good rate I thought. I know I used my credit card when I got to the hotel so I must have given the number to Venere when I booked but I don't remember. The only thing you need to watch for is that the hotel does not bill you in euros and do the conversion to dollars for you instead of your credit card company's rate. You can tell on the receipt if they are doing this. I don't know if this has anything to do with venere or if it was the particular hotel I stayed in. Anyway the conversion rate wasn't too good. But I don't really worry about this, a few dollars here and there is no big deal and not worth getting upset about. I don't make any major purchases so don't lose much.
Regarding the Eiffel Tower, our tour guide make sure we were going down the main avenue towards the Tower just as the lights came on for the first time in the evening. It was wonderful to see the lights start at the bottom and gradually work their way up to the top. Ah, Paris, I must see you again. Miriam - Oregon