Several ways to do this from cheap to $$$$$$$$ Depending on how long you plan to stay there I have a few suggestions.
1st up clean the floor and get some mats, they can be had relatively cheap, and when you move take them with you. If you need to replace a section do it. Hint here Livestock pads and walks, Farm supply place will have them or can order them.
2nd carpet, again cheap if you get the industrial stuff, you can pull up a tile and replace it. Can be found on remodel jobs, put an extra stack in the corner for future replacement.
3rd sealant - like you due for new concrete - I have this in my main garage works well, still have to clean the floor, but no dust etc.... Get the pro stuff and not Thompson's water seal, Building contractor supply will have it. Only down side to this stuff, is you can't paint over it once it is down, you will have to cover with something else if you want.
4th paint, I painted my new shop floor with the homedepot rust-o-ileum stuff. Yeah it looks nice, but an be a pain to clean and is slick if you get liquids on it. Go with beige, the light gray reflects light better, but you see every little piece of dirt, tire track etc... The Beige does not show it that well. It has held up pretty well, it does stain, but all in all it works. I did not have a lifting problem, but YMMV being on old concrete. If you need traction they also sell a mix there from Behr - use half the recommendation. My wife likes the color specs I used on the boat storage side, makes it look interesting, and helps hide stuff. I applied straight grey on the workshop side, so I could see the stuff I dropped, works well for that.
5th - have it done with professional stuff, the Price is expensive but it might be worth it if you are spending a long time there, and don't want to redo it several times. If you have a pealing problem.
6th racedeck etc..... $$$$$$$ but can be taken with, used at the track. etc.....
7th Truck bed liner - seen it done, costs an arm and a leg, but it is pretty strong stuff, and can be had in a tint-able color, so you can have a floor that matches your 914. Not sure my wife would like a signal Orange floor
Of course first things first, get your self a piece of clear plastic tape it down (you must seal all edges to the floor) leave it there 24-48 hours and see if you get any moister trapped under it. If it has anything, then a paint coating will not hold, the water vapor will actually break the bond and cause it to peel, bubble, and lift. thats the first step before you spend a dime on any floor product.