Congratulations Caroline for wanting to single hand a boat on the Great Loop. You'll get many suggestions for the type of boat but I have other sound advice. I was a single woman about 15 years ago when I got into the wonderful world of 'Trawlering'. I too had been a sailor for many years and had also 'graduated' from J World Sailing School, no different from what Annapolis and Colgate taught so, we have some things in common. My husband and I had already attended the basic Power Squadron class (equivalent to the USCG class) and thought we pretty much 'knew what to do' and discovered even that basic course taught us more than the sailing school did. While it taught us some 'rules for racing' it came nowhere close to preparing us for cruising...even though it foolishly 'qualified us' for bare boat chartering! Do NOT consider you are ready to 'Do the Loop' because you went to sailing school! There is nothing worse that being fooled into thinking you 'are prepared'. It is a danger to both you and other boaters out there on the waters!FIRST: get your knees done both at once if you can find a surgeon who will do that (I DO have one here if you're interested,) While you are going through rehab which is VITAL, consider taking some USCG courses on seamanship. You WILL need them! I ended up taking the USCG course for obtaining my 6 PAC license to become a captain. I ended up not taking the exam for many reasons but the course was invaluable. IT was also demanding and hard! You have not mentioned a couple of things necessary to get good replies to your questions: where do you now live thus what classes might be available to you? IT'd help to know what economic bracket you are in to help offer feasible boat suggestions, and how BIG are your dogs? Mine was just 15 lbs but still hard to get on/off the boat. I watched a man anchored off our home on the Ohio River struggling to get a standard poodle on/off a sailboat 2Xa day to go potty. You probably will NOT be able to train an older dog to go potty on the boat. Period! I am assuming you'll want to anchor out a lot? What do you know about the different anchor options? Why is one better for this, another for that? Often you must use more than one anchor and you'll be anchoring on many different bottoms.How well can you read charts?  Can you even visualize what it's like going through Norfolk with a huge foreign freighter barreling outbound and a submarine being escorted in? Do you have a CLUE how many buoys are there and what they mean? We had 4 onboard and were prepared but it was overwhelming the first time.I learned that most sailors do not use the VHF radio much less keep in ON at all times. Do you realize what a danger that is to you and others? Can you even begin to read a radar screen?Few small sailboats have an 'engine room'.  and consider access to the ER a very important concern! Are you sure you know how to maintain a diesel engine? Change the various filters needed?I know, I am raining on your parade but that happens on the Loop too...rain and sudden storms, when you least expect it! you can't see for shit, what do you do? Crossing some of the larger bodies of very shallow water and you're being tossed all over the place??? THAT happened with my tugboat captain at the helm no less! What if you catch a crab line?You must be prepared for all events and be able to handle them, alone in your case. Chase your dream with knowledge and caution, not just blind faith and a lack of knowledge of the obstacles and consequences. Please contact me privately for more.Margery Griffith