The cost of Instagram Ads is dependent on factors such as your overall budget, how long you want to run the campaign and what goals and objectives have been set. There is flexibility when setting up Instagram Ads to set either a daily or lifetime budget which gives complete control over the total spent.
Meta's minimum budget for Instagram Ads is $5 per day, which converted for UK clients is around £4 per day (with today's current conversion rates) and to run this for at least 6 days. Our approach to explaining PPC advertising is that "you are buying data from the platform about your audience which is invaluable, so in order to gain enough data you need to run your campaign long enough for the platform to gather data and to begin to learn who the best people for your ad are".
Yes, the two external factors that will impact the cost of your Instagram Ads are:
Your competition - how competitive the industry is at the time you are running ads does impact the cost. Of course across all industries this does fluctuate.
Seasonal trends - depending on the industry you are in, seasonal trends such as Christmas and Black Friday play a huge part in the cost of ads.