I am also new to airbrushing, I recently got a Badger Arrow 105 for $75 from Amazon. It is the same as the popular Patriot 105 but it has a smaller paint cup. So far it is working well, the main problem is my lack of skill and experience. From everything I have read on forums and seen in videos, you cannot go wrong with the 105.
I am using the 105 for a Me-262 with overal green and brown camouflage on top, blue-white on the bottom, and mottled green and brown squiggles on the sides. Probably not the best choice for a beginning airbrusher! The main hint I can give is practice, practice, practice! Here is a list of other random beginner stuff I learned, I hope you find it helpful.
1. I am using my last remaining Model Master enamels. A 5:1 ratio of thinner to paint seems to work for me. Thinned paint flows better, goes on smoother, has less tip drying, and cleans up easier.
2. Testor's airbrush thinner workes great, but is expensive. I am using Home Depot paint thinner and it seems to work well.
3. Home Depot lacquer thinner works well for cleaning.
4. Air pressure should be around 20 psi. For painting fine details like camouflage squiggles, I experimented with lower air pressure but could not get consistent paint flow. I am sure it is bad technique on my part. 20 psi gave me the best result, but sometimes I have problems with spatter.
5. One of my main problems is controlling the dual action trigger. I try to get a gradual smooth start to the paint flow, but I usually move the trigger too little, then move it too far and get too much paint. I can do it better on a piece of scrap plastic, but when I do the actual model, I get nervous and screw up.
6. The 105 is easy to clean and disassemble, but be careful. I already lost the plunger spring. I got a fast and cheap replacement spring from Spray Gunner.
7. Pipettes are very handy for dispensing paint and thinner into your cup. They are also handy for cleaning the cup, needle, and nozzle. I fill the cup halfway with laquer thinner, then use the pipette to suck, spray and swirl it repeatedly in the cup and needle area while using the trigger to move the needle back and forth. Spray the thinner out of the brush and repeat as necessary. I got several hundred disposable plastic pipettes from Amazon, each one lasts for one or two paint sessions.
8. I don't disassemble the brush after each session. I use the cleaning method described above, then remove the needle and wipe it clean. Then I put the needle back in but not all the way. I gently tighten the needle chuck and put the brush back in the box. Seems to be good so far.
9. A paint mask is important, especially when spraying a lot of lacquer thinner during cleaning.
10. It wasn't easy, but I finally got the overall paint scheme done. My next airbrush step is post shading of the panel lines. I am going to try Tamiya gray acrylic highly thinned with IPA, probably at 15 psi. The goal is to make it so thin I'll need two or three passes just to start seeing it. I am also going to try this technique for faint fluid stains, oil sprayed and misted in the wind, etc. But i have some Taniya Weathering Master makeup kits ready just in case my airbrush skills are not up to the task.