1. Get the longest collapsible hose that you can find. It's amazing where some RV park will put their connections.
2. We have a macerator and it works well, especially, when the sewer connection is really far away and I have to connect my gray hose to extend it.
3. Both sewer systems have their advantages (slinky or macerator). The macerator is slower but cleaner.
4. For the sewer tank treatment, I use the 'blue' liquid and found that I don't really need it as often as I was using it. The only time now that I use it is if I have the coach in storage and I will put it in both the gray and black tanks. For drinking water, we use bottled water. Our coach has two filters for incoming water and our fridge has a filter for the door water and icemaker.
5. If you set a car up with new towing equipment, it will cost about $3,000 for the Blue Ox base plate and connections. Personally, I wouldn't want to use a dolly but everybody has their threshold on what they want to deal with.
Good luck.
MM.