Although the objective and the open space in this scenario are seems pretty easy, it's getting hard when you will find out that you can't take a loan. Luckily, there are some pre-built rides, but the first thing to do is make all the underground paths going above the ground, so everything will be seen more clearly. Now, price the pre-built rides, gentle about $1.00-1.50 and thrill about $2-3. Next, open everything besides the Maze because guests are likely to get lost there and the queue time will be too long even after it has been shortened. What is worse is that the Neptune Ride and Maze cannot be removed, so you will have to listen to your guests later and reduce their prices.
Start slowly, mark thrill and gentle rides on research, and put the missing thrill and gentle rides that are available to build. Price them at the same system, too. Now, if you still got some money, build the Junior Roller Coaster and price it at $5. Now you're going to wait for money, and while you're at it, guests will likely get your park dirty, so place benches around and as well mechanics and handymen around.
After your ride tickets sell will be above $5,000, start researching roller coasters, start building them, and price them at $5 to $6 as well. Make sure to put in a few Cash Machines around so that guests will keep going on your rides. In the end, you will beat your objective with a park value more then needed. You will probably run out of coasters and all the rides before Year 4, so build every type of coaster (notice that there are coaster types that are themed, but is the same coaster, so it's referring to one of them) as your money will run to your pocket.
Eventually, except the fact you don't have any loan, the scenario is pretty easy and you will probably struggle to fill all the space on the island, since it's somewhat hilly, but don't rush to buy space, since it's expensive and you will beat the scenario before that, so the scenario is not that hard either.
If you need money, sell the temple! You can get $40,000 from it.