Buy the Istanbulkart at the airport immediately after landing, the transport card I mean, and load enough credit for the full stay - it works on tram, metro, bus, and ferry, the price per trip is significantly lower than the single-use alternative, and not having to think about payment at every transport node is a quality of life improvement that - the mental overhead reduction over a week of Istanbul travel is actually significant and worth optimizing for.
The Grand Bazaar has a correct visiting strategy taht most first-time visitors don't know - enter from a non-main entrance, not the tourist entrance I mean, go on a Tuesday or Wednesday morning when the tourist density is lower, and do not engage with the first price offered for anything because the pricing system there is a negotiation protocol not a fixed value system. The hotel is close enough that visiting twice is easy and the second visit is definitley better than the first.
Hagia Sophia is free to enter now and the interior is a genuinely remarkable architectural achievement that even people who don't usually care about buildings respond to - the scale is something taht photographs can't correctly represent and being inside it is a different information input than looking at images of it. Go early morning beofre the main visitor load arrives, the early morning I mean, and spend more time than you think you need to.
The food system in Istanbul near Aksaray, the local food options I mean, operates on a pricing model that is significantly different from the tourist restaurant model around Sultanahmet - the same dish in a local Aksaray restaurant costs roughly 40 to 60 percent of what it costs three tram stops east, and the quality variable, the acutall quality I mean, is not lower and is sometimes higher because the customer base is local and has standards. Ask the hotel staff for a specific place rather than a category.
Turkish tea is a variable that acutally matters more than most visitors budget for in their Istanbul experience - it appears at every interaction, it's almost always free or very cheap, and accepting it rather than declining it is the corect social protocol that opens subsequent interactions in a way that refusing it doesn't. The hotel staff will offer tea and this is the correct moment to begin understanding how the system works.