Everything I see in this thread so far is good advice. You should consider a scanner as your first purchase but there is a solution to that decision.
Pulsar, Iray, and Bering Optics are all good units.
The one thing that's not mentioned is Field Of View. When you are using thermal at night you are basically blind beyond the FOV of the unit you are looking through. Generally FOV is determined by lens size but when shopping always check the specs because pixel pitch can affect FOV also.
You need to determine the ranges you hunt at and get a unit that suits your needs. I hunt hogs which means a lot of running shots so FOV is critical for target tracking so I use a unit that provides the FOV I need. If you are a one shot one kill type of hunter you can get by with less FOV in your scope.
FOV should be considered with a scanner also. A bigger lens gives you better long range ID capability but means you must move your head constantly in order to not miss anything in your peripheral areas.
All things considered I will suggest a few units I have field tested for a dealer. They are both made by AGM and I have to say when it comes to bang for your buck they meet that criteria. I have owned at least 10 or 12 units over the years and I currently have 4 I am using so I have a fair amount of thermal experience.
The least expensive scanner I would buy is the Taipan TM19. It has a 12 micron core, adjustable objective and high res screen which is very good for the price point. The 19mm lens gives a decent FOV and even though you can get a higher resolution core and wider relative FOV the point here is cost vs performance.
https://www.agmglobalvision.com/thermal-imaging/thermal-monoculars/agm-taipan-tm19-384
The scope I would look at is the Rattler. They make a 25mm or 35mm so check the FOV and get the one that suits your needs. One point that you can consider is that these units are light and small enough to be used as scanners also so consider the FOV for that application as warranted. They also come with single lever ADM mounts which are high quality mounts with very good POI repeatability.
https://www.agmglobalvision.com/thermal-imaging/thermal-weapon-sights/agm-rattler-ts25-384
https://www.agmglobalvision.com/thermal-imaging/thermal-weapon-sights/agm-rattler-ts35-384
If you shop the web you will beat the retail prices listed at the AGM website.
NOTE: I don't want to get into a tit for tat exchange about how somebody's else's unit is better because I know there are a LOT of good thermal units out there and certainly there are better ones available. I own several expensive Trijiicon units and a few others. I am making these choices based on "Bang for your Buck" for the guys that want to get into thermal units without breaking the bank.