I am changing out the older cellular shades in our place with standard 2" Levelor blinds from Lowe's.

Get a spiral Binder and write down everything in that binder as well as take pictures with your cellular phone.

I’ve been looking into both WiFi and cellular options, but couldn’t find what it would cost for cellular.

They are not cheap and obviously require some kind of cellular plan, but I was able to get them to work using Mint mobile (you need a phone to activate the sim card on first, like an old iphone) Ive had 3 of these up watching a property in Cleveland, OH for well over a year, and Ive only had one issue where I needed to go check on the camera itself, (the plug for the solar panel came disconnected and just needed plugged back in) This camera in particular is nice because its actually 2 lenses that capture the full 180 degrees, so one cellular plan for "2" cameras.

Are there any particular internet options, wireless/cellular, that people are using to manage the smart home features? 

Especially when the investor form he filled out listed his occupation as cellular phone salesman.One day, while golfing with this investor, I inquired about how he was able to accumulate so large an amount of investment capital at such an early age.

If you have a large house with multiple levels you can get Wi-Fi mesh devices that anplify the signal through the house.If your looking for a 5g cellular router Wifi combo then you first have to have a good cellular signal at your property.

i had in mind maybe something solar, independent and cellular so I can install on the beginning and dismantle as soon as the flip is finished.What do you use?

You can use WIFI or Cellular for a security alarm system.

As are cellular towers, fiber, the internet, the local gas station, vape shop, computer monitors, keyboards, search engines, and just about everything else you can imagine.