Regarding your inheritance, you will be glad to know that Estate Duty has been abolished for deaths on and after 15 Feb 2008. So you will not be required to pay taxes on any assets (including property) and cash.
Having said that, note that there are financial implications of inheriting a property that you should be aware of.
If the property you inherited is a condominium, you will now be responsible to pay monthly Management Corporation Strata Title (MCST) fees for the upkeep of common areas and facilities.
If the inherited property was purchased as recently as three years ago, Seller Stamp Duty of between 4 to 12% might apply if you plan to sell the property.
Also, if you already own a property and plan to purchase additional properties in future, you will be liable to pay Additional Buyer Stamp Duty of between 12% to 15%, since you now own more than one property.
Inheriting a HDB flat also has its own rules and regulations, so you should refer to the HDB website for details on which policies apply to your situation.