Looking to replace both the gaskets since I noticed car was leakin oil. Any suggestions or concerns I should be aware of? Is it pretty straight forward? I'm no professional mech but I'm comfortable doing tune up jobs. How many hour labor I'm a looking at here?

 

Assume this is a 4 cylinder.

You might be able to remove the oil pan in an hour. Later Toyota's used gasket sealant in place of a gasket.

The valve cover is much easier to get off. Clean the sealing area on the head and apply sealant to at least the corners where the outboard cam bearings mate to the head and upper surface of the half round end plugs.

After new gasket installation retorque the 4 large spark plug tube bolts holding the cover on several times to fully compress the gasket. If leaking now might try retorquing the nuts. 33 ft lb.

 

local auto parts store guy sold me a rubber valve cover gasket and he said I did not need a sealant. Should I still apply sealant?

 

You can try it without sealant.

Sealant is cheap insurance against leaking and outlined in the manual. It is spot sealing of the corner areas where the bearing cap meets the head and on top of the half plugs.