For Lovis' tower, there are some ladders you can climb up to get access. Once you get into one part, keep an eye out for levers to open the gates (a couple are on ledges you need to jump up to). From the front gate you can also edge around the left side and jump over into the tower.
Someone mentioned using cheatengine for unlimited gold, but I've never had an issue with lack of gold in the game. I didn't buy many potions and the majority of my equipment was found or from quest rewards. Once you get the battle tower gold easy to get fairly quickly, anyway.
