the bear II wrote:
1 an alternative since the TT will be left in place is to have it delivered to your parents house.
2. 28ft will work
3. best bet is to tie into your parents sewer/septic system if possible. Alternative is to use a macerator pump to move the stuff from the holding tank valves to a clean out connection at your parents house. Last resort is to use a blue tank with wheels designed for emptying holding tanks. Once you fill it you can take it to a dump station to dump it or if real careful dump it in a toilet (be aware this smells bad).
4. maintenance is about the same as a house. If you do regular routine maintenance you won't have as many problems.
5. Most TT owners manuals are a collection of manuals for all of the appliances and components used in the TT. The manufacturer will have an overall manual to show how TT related items work. Best source is to have the seller show you how it all works and take good notes or video.
Have fun...good idea to give you and your parents some space.
I use a Sewer Solution and 50 foot of 1" PVC to hook to my sewer clean out. Works fine , much cheaper than macerator. Don't leave the dump valve open, wait until tank is fairly full, then dump.