Pied Piper: As RW wrote, you are not going to find a 4.5 amp solar panel for $60. I use a cheap solar panel, approximately 1 foot by 14 inches that I bought at Harbor Freight, to keep my boat's Size 27 battery charged. It has a whole week to put back in what I take out on Saturday and Sunday. I do use an autopilot which is probably the biggest draw at approximately 1/4 amp. Anyhow, this little solar panel does do the job, and the only time I recharge my battery with a charger is when we are sailing for a week or two, sailing every day. I do have the output from the solar panel going through a charge controller, but it is small enough that I probably don't have to. It should be noted that your battery will last much longer if you have it on a solar panel and it doesn't get drawn as low as it would get if you charge it and draw it down deeply. If you do some research on this you will find that it is not recommended to draw a battery below 1/2 down, and there are voltages associated with this, but I don't have them here.
I used to use a bigger solar panel, but my son took it to use on his C-22. It can put out about 4 amps, I believe from some measurements that I took, but you can see that it is a serious panel. (I just like to show that photo. We were sailing into into St. Mary's Maryland at the time.) He mounted the panel on top of his Bimini top.
I do recommend a solar panel like the one that I bought at Harbor Freight. It is item # 41144, and is currently selling for $49.99, but I think that I paid less for mine. I did put little feet under it that I made from rope, (after the plastic ones melted). I keep mine on the cockpit floor, under the tiller during the week, and put it into the compartment behind the fuel tank when we are sailing. It is very convenient. There were times I took my battery home to charge it, but I haven't done that in years.
Aldo