The following examples are all grammatically correct and commonly used. Have a read of them and draw the conclusion by yourselves. It should be quite self-explanatory:
---The situation where both "in front of" and "out front of" can be used:
"A person is standing in front of the store (or house, building,etc)" is the same as "A person is standing out front of the store (house, building ,etc)"
---The situation where only "in front of" can be used:
1. One more word needs to be added IN front of the sentence.
2. A person is standing IN front of the group (crowd)
---The situation where "out front" is used:
Where is John? He is (standing) out front.
---The situation where both "in front of" and "out front of" can be used:
"A person is standing in front of the store (or house, building,etc)" is the same as "A person is standing out front of the store (house, building ,etc)"
---The situation where only "in front of" can be used:
1. One more word needs to be added IN front of the sentence.
2. A person is standing IN front of the group (crowd)
---The situation where "out front" is used:
Where is John? He is (standing) out front.