Hello, Blackstamp2023 from Ecuador,
Welcome to the forum. What a wonderful gift your grandfather left you. You are off to a great
start in your new hobby.
On November 7 of last year I purchased on
ebay a 40lbs. box of used stamps on and off paper for $29.99 plus shipping. The box held approximately 80,000 stamps which were similar to and including many of yours. If you run the numbers, that comes to 25 stamps for a penny....in my book, a good deal. I worked on them over the course of our winter.
I had a good collection as a youth and re-entered the hobby 8 years ago at age 65. Stamps, sports, boating/beaches, and travel keeps me breathing. My Dad was a stamp collector and he was healthy until age 100 (The FDA may not like me to infer a cause and effect relationship here, so I won't

).
Good luck and much happiness with your new hobby. Use it as a source of enjoyment but avoid the "stamp collecting path to riches" (in my humble opinion).
Sincerely,
Greg