In order for me to properly assess what you have I will need to know the size and see images of the front, back (do not remove from frame) and a clear, in-focus close-up of the signature.
If you had already attached images to your initial posting, they are not showing for me here on my end.
Please send the photos at your convenience. There is not an extra charge to provide more pictures here.
Thank you for the images. Please allow me some time to look these over for you.
Thank you for the dimensions.
Thank you for your patience.
Currently, maritime paintings by the 20th century painter, T. Slowsky are selling at the high range of $550 - $800 on today's auction market, however a majority are selling in the $200 range. His works have not yet caught on in the secondary market and the sale prices are nearly equal to the original prices when the paintings were first offered to the public when new. This is common in the art market. The suggest insurance or replacement value is $1500 - $2000.
Unfortunately art does not exponentially rise in value over time after purchase. It is a common misnomer in the art world. Art purchasing is speculative, if there was a guarantee that artworks always rose in value after purchase, then all art would always be bought as soon as it showed in a gallery or studio.
I can send you links to recent auction sales to show the recent sale values.
This one sold in 2014 for $200 against a $400 - $600 estimate:
This one sold for $700 in 2013:
This is one of his more monumental paintings that carried an $800 - $1200 estimate in 2009, but did not sell:
Here is a link to a list of some past auction sales:
Here is a link to one that sold for $390:
This sold for just under $65:
This one carried an estimate of 100 - 150GBP (British pounds) and did not sell:
By appraisal standards set forth by the IRS, there is only one view to be taken and that is fair market value, or FMV. FMV is based on the transparent auction market, which reflects the prices at which the buying market is currently paying. At gallery or studio sale, the price is perceived value, which can be any price the seller places on it. As an owner of an object, you can ask any price you please on any item you own, the key factor being finding a willing buyer at your price point. The value that I provided as an appraiser is a benchmark based on actual sales, but again, if you are selling this, you can place whatever price you feel you should get for it.