Hi Charlotte, Try out Oyo rooms as you coming on business trip if I'm not wrong, as these rooms are very comfy staying with good number of facilities! Also try on Make my trip app you will find great stays with best prices
Don’t stay in paharganj area..it is although cheap but you might not be comfortable..you should better stay around new delhi airport..it has the best hotels and they are not too expensive if you book in advance..Good deals are like Holiday inn,ibis,redfox,lemon tree..you’ll get quite cheap deals on various websites if you book timely..so go ahead and check reviews about the hotels..
By the way HOLIDAY INN provides complimentary pick n drop to airport..confirm this if you book it