When Tawny Kitaen enters the party in disguise, she's wearing a blonde wig. When Tom Hanks has her in the bedroom, she pulls the wig off and her brunette hair is straight. In the next scene as she's leaving in a huff, her face is very heavily made up and her hair is curly.
The 1971 Plymouth Satellite being serviced on four jack stands where the undercarriage falls out - Mopar B-bodies (produced until the 1979 model year) do not have a full perimeter frames; Chrysler products produced in the 1970s were unibody vehicles with the exception of its 1971-77 full-sized C platform vehicles (Imperial, Fury, Monaco) which had a bolt-on subframe. The only full-framed Chrysler products produced in the 1970s were Dodge light and medium duty trucks.
After Cole grabs Debbie and hijacks the city truck, Rick and the others get into the bus and give chase. When the bus pulls out of the alley it says "St. Gabriel's School" on the right side and ARA Transportation on the left. When the bus pulls up at the movie theaters, it says "St. Gabriel's School" on the left side.
Although Rick has the bus valet-parked when the gang arrives at the hotel, he would have had to take it out of valet parking when they go to spy on the ladies at the strip club. So it's possible that he simply parked it in the alley when they returned and left it there, which would explain why the bus is standing there the next morning when everyone is running out of the hotel.