2008 180 Challenger won't start... again

[fegnomashic]

I have a 2008 180 Challenger. I have been in and out of the shop since I got it.

I winterized it through the dealership last year, kept it inside my garage all winter, but when I went to put it in the water it wouldn't start (the battery was charged).
Brought it back to the dealership, they "fixed" it (not quite sure what they did as I am not very savy with mechanical things), got it back and it wouldn't start again. This time they had forgot to hook up something. I got it back again and it started.
I put it in the water and docked it on my lift as were were on vacation for 3 weeks. Got back today. Checked the battery (actually two batteries because I keep one in case). Both were charged so when I try to start nothing. Not even the dashboard lights up, no horn, no pump, nothing.
So I don't have a clue where to begin (other than I have to bring it back to them AGAIN).
Oh I also winterized my 3D-Di with them and it won't start either (with a fully charged battery) but I won't even get into that yet.

Thanks for any help that can be given.

 

[RFoster130]

Try to check it out yourself. Check to make sure the battery connections or tight.

 

[fegnomashic]

I did that. Even had my neighbor double check and it was on tight. I looked at the fuse box and didn't see anything obvious. The only thing I was wondering is if there can ever be a bad connection between the key thing and the starter knob thing?