Our free advice
Use Jeannies ShopnDrop for intial unit stocking, you only have a wk, saves time the 1st couple of days
If you go out at night and want to cab - try Wilfred Brooks a sponsor, nice man, and dependable
Get the SXM nights booklet at the airport, has a map, as will your rental.
I would not go to Anguilla, you only have a week, eventually you'll go, but instead I suggest a round island boat trip. You'll see / go to beaches from a different perspective - lots of good tour operator choices for sail or power.
Beaches - Orient, Mullet, Friars Bay, Anse Marcel, all different
SMYC for happy hour, go the their web site to get the bridge causeway times so you can keep the info in the car so you don;t get caught in the lineups
Marigot, coffee and croissant at a bakery, walk around the market, we go the french linen lady, there is local jewellery, but double check some is local as in sold on island, some is local as made on island! - Note the Marigot Marina is not by the ocean - our 1st time we kept walking around thinking we had missed the resto we wanted to go to, until someone directed us the marina which is on the lagoon side, duh ....
Tons more won't even start a resto debate
Read the trip reposts in the archives and have fun
J&B