New ball python, need some knowlegde.

Do you know what your ambient temps are during the summer? If you are at least in the 70s you should be fine with just the UTH, and limiting ventilation in the cage. You certainly can do a lamp dimmer for both an infrared bulb and the under tank heater. Just be aware that if you position the bulb directly above the UTH, you will be not only increasing ambient temps, but adding to the hot spot temps as well, likely pushing it out of the acceptable range. To avoid this you can offset the bulb away from the UTH so that it is just contributing to ambient temps only. Keep in mind though that with two heat sources you are going to be drying out the enclosure significantly, and will need to make sure your humidity is on par. Humid hide boxes, basically a Tupperware container packed with damp sphagnum moss works great.

I live in Canada too. I find it harder to regulate the temps in the summer than the winter. A thermostat is a better idea IMO for the UTH. The lamp can be put on a dimmer unless and until you decide to get a thermostat for that too. A thermostat that has two probes and two outlets so it can regulate both the UTH and the lamp is ideal. I don't know if you have any budget concerns.

A decent thermostat is going to run 100$+. Don't even bother with the pet store plastic zilla thermostats. They are absolutely junk. A lamp dimmer will do you just fine. You should be checking your temps with a gun frequently anyways. IMO a thermostat is overkill for a first time BP owner with only one animal. Spend your money on quality feeders or save it for a possible vet visit in the future.

Little update, yesterday, after a costly visit to the pet store to get some accessories for the enclosure, I cleaned the terrarium really well and then I set everything up. Now the smell is gone and everything's good. I had no problem taking her out of the enclosure and putting her back in even if it was only the second day she's been here so that's good.

I haven't seen her outside her hide since I put her back in yesterday around noon, not sure what it means but everybody seems to say it's normal and it means she's happy. Just as I was typing that she just came out, looks like a little bit of exploration.

I'll try and post a picture tomorrow of my setup but yeah I seem to really need both the lamp and the heat pad because the temp hasn't gone above 87 so far. I also need to mist alot like 4-5 times a day and I struggle to keep 55 on the hygrometer (using exo-terra forest bark fir bark).

The thermo-hygrometer sensor is located on the hot side about halfway up the eclosure, I put it slightly behind an artificial plant so I don't know if it's being obscructed or not but I need to test I guess. I opted for that since I didn't want to spend too much on a heat gun but I may end up getting one anyway...

Other than all that, tomorrow I gotta go buy another hideout for the cool side and then the "practical" setup will be pretty much done with, all I'll have to add after that is some more decorations.

Sounds good but I suggest putting the sensor at the bottom of the enclosure, under the hot hide since that is where your snake will almost always be. A sensor is supposed to be between the bottom of the enclosure and the UTH, outside of the enclosure.