Need help with form development in Drupal.

Hello there, I need help with developing a form in Drupal. I am sharing some of the information. The purpose of the form is to make booking for services offered. STEP 1 - The form is dependent on what the user selects. So, the user gets to select one of the choices from a radio button. This radio button has only two choices, say Option 1 or Option 2. STEP 2 - Depending on the choice made in Step 1, a dropdown field is show. If Option 1 is selected in in Step 1, the drop down has few choices (e.g. 1, 2, 3, 4 ... 10). If Option 2 is selected in Step 2, then the drop down has few choices (e.g. A, B, C, .... L). STEP 3 - The Rs. value are just examples. If 1 is selected in STEP 2, then user is shown that the cost is Rs. 100 (Fee 1) and Rs. 200 (Fee 2) and the total cost is Rs. 300 (Total). If 2 is selected, then the cost is Rs. 500 (Fee 1) and Rs. 25 (Fee 2) and the total cost is Rs. 25 (Total). This goes on for 3, 4, ... A, B,... L. It would be great if this values can be managed in a lookup/backend table so that it can easily modified in future. STEP 4 - The user gets to select the date of the service from calendar. And clicks on Next button. STEP 5 - For any specific date, only three submission/booking is allowed. So, if there are already three bookings on the selected date, the system will inform the user to booking is not available for that day and he/she needs to select another date. If the date is available for booking, the next page will display some information about the person (Name, Address, phone, email address). And then submit. Note: The above may include few fields more based on the user selection but it is not complex. Lastly, we need to integrate this with Paypal account to complete the transaction. Drupal setup will be provided. Looking forward to hearing from you.