Interior fuse keeps blowing

I just recently purchased a 2011 Primetime Lacrosse ultra light. I live in Florida. It was delivered 2 weeks ago and is currently sitting in my driveway.I was able to open the slides and set it up. I went and checked the grey water/ black water ect, and noticed the battery was low. So i charged the battery and later i went and bought a 12g extension cord and plugged it into the house.I knew not to run things due to limited power. So ive never turned on air/heat or microwave. When I plugged it in, I noticed that the main power cord was wrapped in electrical tape. (Notified them and they said I needed to replace it, they would be happy to price it for me). I did turn on the stereo. And a two lights while cleaning it. (Arrived uncleaned). I know it was in some sort of accident while they were delivering it.One fender was completely ripped off and the other held in by 2 screws. Slight damage in front and ding on one slide. I asked the dealer for two fenders. And i would put them on if he sent them here to my house. At first he only agreed to one fender. The awning motor didn't work at walk through. Neither did the tv. And number 9 fuse was blown but said they would replace. When it arrived number 9 fuse still had a light. I checked the 15amp fuse and replaced it.2 hours later it blew again... I replaced it with a 20 amp fuse because the box says not to exceed 20amps.. but once again it blew. I tried turning stuff on and off. Minus air heat water heater microwave ect.but couldn't get it to blow. I left it and checked it 2 hours later and same #9 red light. Basically long story short. I'm already eating the cost of 2 tires a spare. The awning. Replaced the water line to the refrigerator (no water line) but they did finally get me keys to the outdoor kitchen and undercarriage, so I can take that off my list. and with needing to purchase a new TV. The only one it came with doesn't work. this is adding up quick. I still haven't even finished paying all of the down payment due on the 1st. I have an ohm meter and line chaser. Tried everything I know to do. The refrigerator still works with #9 showing red. I did have to email manufacturer for owners manual hoping to get a diagram of that load is on the fuse. They emailed me a generic owners manual with no real info in it. I don't see any markings on the fregerator so I don't know what kind it is. After they sent the tech here to my house to fix the main power cord. I seriously doubt I can get them back out here. The main guy just yells athe me .. really yells and just hangs up on me. "I don't have time for this " he says. I'm lost... I love my new rv... and im going to make the best of it but also want to be safe. So much for my extended warranty I bought. Alot of places around me won't even look at it they say it's only been 2 weeks. We dont do warranty work on rvs that we didn't sell. I have seen you all answer great questionsite on here. So its time to turn too the smart people. Any help is sincerely and greatly appreciated.