Most treatment specialists use Advion. You can buy a 4 canister pack for about $30-40 on Amazon; just make sure its from a reputable seller and to read the reviews as there are a lot of fakes or people selling old stock. Youʻll notice a reduction in activity for most ants within 1 week and they will disappear in about 2-3 weeks.
If you have carpenter or pharoah ants or ants resistant to advion, pick up Maxforce Fleet
If you want to go the spray/treatment prevention route, buy a product called Taurus, which is a cheaper version of termidor and also what a lot of treatment specialists utilize when they overcharge you. Both are primarily utilized to treat termites but are effective against a large number of insect species, to include ants, roaches and centipedes. Make sure to follow the application instructions and only utilize outdoors.
If you want the "safer route", boric acid and sugar/honey if ants are in their sugar phase, boric acid blended with boiled or canned chicken if they are in their protein phase. Donʻt waste your time with borax as what youʻre after in borax is the sodium tetraborate, which a salt form of boric acid and significantly weaker and less effective than boric acid. If you canʻt find or donʻt want to buy it online, you can usually find boric acid at Ace Hardware as a roach and ant killer; just read the ingredients list to ensure that its 99% boric acid.
If you go the boric acid + sugar route, always dissolve both in hot water. If making the protein mix, you can blend or smash until well integrated as best as possible.