I am going to assume that you wee boat is GRP and if not then I show my ignorance as the numbering of the vessel and its related age.
I am in the middle of do a repair and repaint job to my Wayfarer W6657. Like yours it has had a few knocks and scrapes over the years and there have been a few hull repairs carried out over the decade to keep her water tight. Thankfully there are no current holes as far as I can see. Like you I am relatively green to the whole sailing boat owner thing, but over the past few months have learned a lot from asking around and chatting to people. Here has been a good source of info as well. What you will find in your journey of discovery and collation of boat knowledge is that there never seems to be one way to go about things, people always have the own opinions and ways of doing things. So it is best to read digest as much as you possibly can, time allowing and then go and making your own informed decisions.
So here is where I am at at the moment. I have totally stripped my boat down to the bare hull. The wood work has been sanded back to the bare wood treated and to date has had four coats of yacht varnish applied, aiming for six. This is all a bit time consuming due to the climate at the moment and I am allowing a longer than normal period for each coat to cure.
The deck has had at least three coats of paint applied to it over the years, none of which to my knowledge proceeded an undercoat, so I had a three tone scratched boat. Last Autumn I spent the the weekends sanding this all down using an electrical orbital sander to using 60 – 80 grade discs. I then used 120 grade wet and dry just to take the roughness off, but allowing a good key for the undercoat. This weekend I have just started to apply the first undercoat, Pre-Kote (International Paint), this was recommended to me by a couple of people and endorsed buy a local marine retailer. Eventually, weather permitting the topcoat will be TopLac. Because my boat is not going to be left in the water for any period of time as it is to be kept on hard standing, it is possible to use the same paints below the water line. And a small tin of this stuff goes a long way.
The inner hull was a bit of a mess too, so I have given this a good rough up and repaired the areas where the poorly fitted make shift floor boards were rubbing. This is all ready to be painted, which I plan to do in the next couple of weeks. Once the decks are undecorated and prior to top coat, I plan to turn the boat over and work on the hull. Again I think this has previously painted. I have been advised to rough this up all over with 60 – 80 grade sand paper, similar to the deck to provide a good key. Then apply two undercoats of Pre-Kote. Sanding with fine wet and dry in between. And the finish with the TopLac final coat.
WaterTite (International) is a suitable filler to use both above and below the water line. It is easy to sand and can be painted over with no problems. It is often hard to get things perfect on first time of filling, so a second touch up may be necessary. It all depends on your level of perfectionism I guess.
Hope this helps and like I say, other may have a totally different approach. The shoe string budget is the difficult thing to keep a hold of. I suspect my budget is going to go out of the window shortly, possibly because I am hooked on my little W6657 and want to give her a decent life despite her age.