Create a Wordpress Template

I am a volunteer with a not-for-profit, no kill animal shelter in Quebec that has a WordPress website. Every year, we raise funds for the shelter by "selling" one of the 365 days of a 12-month calendar to supporters who want to feature a photo of their companion animal in a printed calendar. Up to now, another volunteer was in charge of the bookings. He would be contacted by a supporter, would check to see if the date was available, would collect the $30 (cash or cheque) and would secure the image of the animal (digital or print) which he would pass to the volunteer electronic artist. He would record the name and address of the supporter and pass the information to another volunteer who would issue a tax receipt. We would like to modify our existing WordPress site to allow supporters to check availability of the date, reserve and pay for the insertion (via PayPal), upload their photo and receive a receipt by email. We would give the supporter the option of reserving and paying without uploading to accommodate those who want to mail-in a printed photo or those who want to reserve the space but are not ready with a photo. We are hoping that there is a WordPress plug-in, similar to what may be used by a Bed&Breakfast that can be used to do some or all of the above. Unfortunately, the volunteer who helped us with the design of the site is no longer able to help us out. We have good intentions, but have no experience with WordPress and/or web design. If you are able to help us, it would be greatly appreciated by the volunteers and the shelter that helps so many lost or abandoned animals. We don't have discretionary funds so your fees would have to be covered by "passing the hat" and collecting from the other volunteers. Thanks in advance for the consideration. I have included a visual of one of the pages of the calendar.