To cover asbestos or not?

I'm no expert, but IMHO the safest option is to remove 'em, which'll pretty much cost you an arm and a leg. Not so much for the labour, as for the sealing of the area during removal and final disposal. It's still cheaper than being sued over health hazards.

If the tiles are in good condition, no breaks or powdering, you could get away with covering 'em, provided whatever you cover 'em with doesn't involve any damage to the tiles. Preferably not even screws. A floating floor with an underlay would be good, but raises the floor height. Gluing to the tiles could work but wouldn't be my choice. Even good carpet'd do, but all of these are really only temporay workarounds in the long run... leaving intact asbestos in walls or roofs is one thing but floors tend to be high wear areas.

The problem you'll be left with Angel is that when you sell the units the buyer will know the asbestos is there only if you tell them. They will then walk away or reduce any offer. If you have a good conscience you'll tell them - caveat emptor notwithstanding - if not you will be subjecting any future owner to risk.
Similar tiles were used in a hospital here in Tasmania and when it was demolished the tiles, though low in brown asbestos, had to be removed by the specialists.

If I was you I'd take no chances, do the right thing and spend the money to get rid of the stuff.

Here in Tassie (at least in my municipality) the regulations allow an individual to remove a maximum of 20m2 per day provided you wear a full body suit (one of those zip up disposibles will do the job), wear a chemical filtered dust mask and wrap the asbestos (the tiles) in heavy plastic. Most councils will pick up and dispose or Collex are registered to handle the stuff.

You'll sleep better knowing you won't be responsible for someone developing asbestosis or mesothelioma, both fatal.
Cheers