FLG
I have guns from HF, DeVilbiss, Sharpe, Binks, Eastwood and a couple others.
DeVilbiss FLG 4 is about the best blend of price : performance out there right now if you ignore the HF purple gun. The Eastwood Concourse 2 is slightly cheaper but doesn't include other fluid tip sizes like the FLG 4.
If you are going to be spraying more than a few sessions, the 3m PPS (or the DeVilbiss dekups) system makes clean up a ton easier and you can spray upside down. Especially useful when painting the interior. It's another $100 by the time you buy the stuff and the adapter though.
What compressor do you have? The HVLP guns use a lot of air.
What he ^ said. I have a FLG3. 1.3 and 1.8 tips. Serves me well. 3M 200 micron PPS cups. I got the gun used so I saved a bunch. 1.3 is for final color. 1.8 is for thick primer. I use 6oz cups for most work and occasionally the next size up.
A few "tips".
Buy a Hobby Air. Use it when spraying anything. Plus you look like an astronaut!
Buy a 3M mask with #60926 filters. Date the filters. Keep it in a zip bag with desiccant when not used. Use it when not spraying but products are open. Replace filters annually or sooner if used often. Used filters are fine for dust but they loose the organic filtering in time and you won't know.
Buy a RTI Micro 1/4" regulator. Set and forget. Connect it at the gun.
HF red disposable filters are ok. Use one at the gun, between regulator and hose to catch water and oil. Date or mark it every use. Replace if it shows any signs of contamination passing through or difficulty blowing through it. They are cheap.
Buy big hose for HVLP. They use a lot of air. Don't use it for anything else. If the compressor has an oiler for tools, take it out so it can't contaminate the new hose.
Buy a box of syringes. Grainger sells the rubberless 50ml catheter tip. Excellent for measuring paint with zero waste. No rubber means no silicone contamination.
https://www.grainger.com/mobile/product/NORM-JECT-All-Plastic-Syringe-19G341
Rubber syringes are fine for measuring thin stuff like catalysts and reducers. I remove the plug and hold a finger over the tip. Product flows out easily.
I label the syringe and apply packing tape over the label and markings. Solvents will wipe the markings right off.
Read every thread Dan Horton posts especially how to Cut & Buff.
Find someone with a detailed blog on paint. Feel free to check mine out. There's are pages dedicated to fiberglass, paint and cut & buff.