Not sure what you mean by taking care of, there are 2 aspects - dumping and cleaning.
Dumping is fairly straightforward, but finding all the parts you need, or at least want, which work together can be a bit of a challange. Here are the parts of a dumping system: 1) Disposable gloves (safety), 2) clear 45 or 90 degree elbow (conveniance), 3) 2 sections of hose totalling 20 feet or more (required), 4) some form of support so no dips in hose (conveniance) and 5) a good adapter for most of the dump stations out there (required).
For 3, get the heaviest duty stuff you can find and afford. The lighter it is, the sooner it will develop pinhole leaks. For connectors, you can go with the bayonet fittings (you will need at least one to connect to the trailer), but be sure that it fits snugly and securely; there is at least one brand out there (the blue one) which leaks and/or lets loose under usage - not good at all. Once you are connected to the trailer, the blue press fittings are pretty good and versatile, and the blue elbow is the best I've found. The red system seems pretty good too, but it doesn't work well with non-red parts.
Another option which is pricey but conveniant is to install or get a powered macerator pump. There is a water powered macerator, but the first and only time I used it, it clogged up, leaving me in a terrible pickle.
To clean the tank, there are 3 basic methods. 1) stick a wand down the toilet and spray the gunk loose (cheap, annoying to use), 2) have a spray jet installed in the tank (medium price, easy to use, chance of leakage if not intalled right) or 3) backspray through the dump port (variable effectiveness, can get pricey, easy to use, no modifications to RV) For the last one, you replace your clear elbow fitting with one which has a water inlet (AND AN ANTI BACKFLOW DEVICE). One of the choices has a jet which goes back up the dump pipe to knock junk loose and the other has a second valve which allows the tank to be backfilled. I made my own combination of these 2 designs for most effectiveness.
Mark, 2 water inlets? That sounds unusual. Did it also have a 3" output hole?
It is possible that what you saw was the 'sewer solution', a water powered macerator pump. It takes a hose in (for water and 'power') and a hose out (included, for ground up sewage). This is a great concept, and some people swear by them, but the first and only time I tried it, it clogged up leaving me in a terrible mess (literally).
All the non-macerator angles I have seen have 1 and only 1 water inlet, 1 sewage inlet and 1 sewage outlet. The water input may provide a jet of water back up the dump pipe, which can work well if the pipe is a straight run. Or it may just be a water source, to allow backfilling the tank (not as effective but immune to pipe geometry).
The 'anti backflow valve' screws into the water inlet, usually a black plastic thingie about 3" long and 1 1/2" in diameter. Then you screw the hose into it. If you look closely, you should see little holes or slots around it. This is where the water comes out of when the pressure is relaxed, preventing fouled water from being sucked back up into your good water source. You can buy these plastic ones separately for a few bucks, or in brass for lots of bucks. Just be aware that whenever you turn off the water (or significantly change the pressure), THESE DO LEAK, by design. And what they leak could be contaminated. Indoor use should be avoided
Being of the opinion that anything can fail and will unless you are prepared for it, I actually use 2. 1 on my sewer elbow and a brass one at the other end of the 'gray' hose (which literally is gray to avoid mixing it up with the white 'pure' water hoses).