Glad you have the knee pads - that would have been my first recommendation. Second the swear box which will allow you to save up for your kids' Xmas presents.
Practical things. The seams are shallow. breaker tape not needed - that is used on thick (9mm+) teak where it is important the caulking sticks just to the sides not the bottom to allow for movement. Not sure of your boat, but some early Bavs had ply backed panels and thin teak veneers, but you won't know how deep the seams are until you clean some caulking out. Depth of teak remaining will determine how much you can safely sand. Two schools of thought on caulking. One is over fill and sand off the excess other is to mask and remove tape before caulk sets. I tried both on my teak deck project (still got the hard knees after 8 years, even though I had toughened them up beforehand by laying a large decking!). I ended up preferring the latter mainly because the Saba that I used needed a lot of sanding. You will find that 220 won't make much of an impression - I used 120 on a belt sander. The downside of masking is that you have to deal with lengths of tape with caulking attached which have a mind of their own, particularly if there is any breeze. Gloves and a deep cardboard box alongside with a brick in the bottom to stop it blowing around I found the best way of taming it. Then let the caulk cure in the box and you can just scrunch the waste up.
Finally go easy on the sanding. The teak is poor quality plantation grown (what do you expect for the price), not very thick, and after all these years exposed to the elements will be impossible to get flat overall. Best you can hope for is keeping it looking respectable for another 10 years or so.
