Is it brick out building or a shed ?.
Do they have access to out side ?.
How big is enclosure ?.
I have two indoor groups of Meerkats that have access to the outside via a tube system. They only have access to this when I am around though.
A meerkat enclosure can be as simple as a sand pit structure. The more Meerkats the larger it should be.
Mine live in a complete enclosre ( 4 sides, floor and roof ). Through a number of tubes they have access to a number of nest boxes that I also have easy access to. I thought putting the tubes on would simulate a tunnel system into nest as in the wild
. They use one nest box as a bed area and another as a toilet. There are heat bulbs for the winter months and have have lighting to. They have a sand pit area with logs etc as they love to dig but the rest of the substrate is wood chippings as it is easier to clean.
If they have no access to the outside I would definately suppliment the diet with Vit D3, mine get this any way.
Diet is pretty straight forward, defrosted mice, small rats, day old chicks, chicken wings, legs, drumsticks, moreo worms, locusts, mealworms, dried dog and cat kibble, carrots, broccoli, cauliflower, corn on the cobs ( large and small ), peas, beans, apple, pear, oriental pear, mango, papaya, banana etc. I supplement the diet with a calcium and vitamin supplement a couple of times a week.
Sorry can't help on the breeding side as I only got mine last year, hopefully they will breed this year.