From your code, I assume you are talking about mapbox.js, which is a derivative of leaflet.js

If so, I think what you are looking for is leaflet layer groups

So, in your case...

var featureLayer = L.mapbox.featureLayer({
   "type": "Feature",
   "geometry": {
   "coordinates": [
      '.$long.','.$lat.'
   ],
   "type": "Point"
   },
   "properties": {
      "title": "'.$business_name.'",
      "description": "'.$address_1.', '.$address_2.', '.$address_3 .', '.$postcode .'"
   }
   });

var accomodation = L.icon({
   iconUrl: '/img/pins/day-and-night/accommodation.png',
   iconSize: [46, 62],
   iconAnchor: [8, 60],
});

var layergroup = L.layerGroup([featureLayer, accomodation]);

layergroup.addTo(map);


Adding custom icon and marker data together using Mapbox
For example, 
Starting a new business requires a lot of work. 

What would be an adjective in: Starting a new business is _. 
