Sales tax in Costa Rica is 13%. Restaurants additionally charge a legally required 10% service fee, which is the service tip that goes to the wait staff. Restaurant menus will usually state if sales tax and/or the service fee are already included in the prices; otherwise they will be added onto the final bill. If you should receive very good service by the restaurant staff, it is still customary to leave an extra tip
At hotels, it is common practice to tip housekeeping $1 to $2 USD per night, and bellmen $2 to $3 USD per person during your stay. For large groups, these tips generally are already included in your pricing.
Local guides and drivers will be happy to receive $1 to $5 USD per person per day.
In general, the amount of any tip depends upon your satisfaction and is subject to your own discretion.