The first time you've set eyes on your forever pal, has it ever occurred that the responsibility that came with them would be a bit... messy? Potty training, potty cleaning, potty, potty, potty.
When I got Peanuts, who was my first indoor potty trainee, I had to clean every spot she peed and pooped on. I thought soap and water was enough. But then she came back to the same spot and it drove me crazy. I tried finding odor removers from our local hardware store and mall but there weren't any available back then.
Eventually, I scoured the net for easily obtainable cleaning items. This were the ones I used.
1. Cloth or Paper Towels to absorb the dog pee. If left alone, it could promote bacterial growth and a very piercing ammonia scent.
2. A 1 part Domex All Purpose Cleaner (it was available in the grocery store) mixed with 10 parts water to clean the potty spot with the use of a spray bottle.
This is to remove any unwanted smells the human could still take a whiff of. I also use a scrub rather than just spray it (as microscopic fecal matter can still be lodged on the floor, especially since ours is mostly made of wood). If you're not into scrubbing, you may also try a vacuum cleaner.
3. There are different home-made odor removers in the net but I prefer the use vinegar with water to mask their potty scent. You can also mix that with baking soda but vinegar (white preferred) is enough to ward them off from sniffing the area around.
4. Consistent praise whenever you catch them doing their business in the potty spot.
By the way, when making a potty spot, don't ever EVER forget to place a plastic covering between your floor and the indoor potty area. I made the stupidest mistake by only using a single large plastic tray with news papers on top as my potty spot. When Peanuts had accidents, I had to clean the floor over and over again.
For more information, here's a more comprehensive link to read.