Swagger1889

I'm going to go with 5.0 for the creases, small edge tears and stains.
 

I agree, just looking at the pics before reading the above reply VG/FN 5.0 is what popped into my mind.
5.0 VERY GOOD/FINE (VG/FN):  Back to Top
An above-average but well used comic book. An accumulation of bindery/printing defects is allowed. Minor to moderate cover wear apparent, with minor to moderate creases and/or dimples. Inks have moderate to low reflectivity. Blunted corners are increasingly common, as is minor to moderate staining, discoloration, and/or foxing. Stamped or inked arrival dates may be present. A minor to moderate spine roll is allowed. A spine split of up to 1/2" may be present. Staples may show minor discoloration. Minor staple tears and minor stress lines may also be present, as well as minor rust migration. Paper is tan to brown with no signs of brittleness. Centerfold may be loose. Minor interior tears may also be present.
I have no idea what the cost is to have a book graded but the average eBay selling price for this book in VG/FN 5.0 based on recent sales of books in that range (VG+ 4.5 $72.00 and a FN- 5.5 $112.00) is about $90.00 +/-.

Nice key could even be fine minus‼️‼️?

its a math question.  and a risk preference question. and a preferred return on investment question.  you've got to do your own math and figure it our for yourself. 
look up raw prices in completed sales on ebay.
look up CGC graded prices on ebay AND use GPA Analysis (google it, its like a history of CGC sales)
Look up CGC submission prices on their website, make sure you factor in shipping and insurance if applicable
make sure you factor in any other selling fees or paypal fees, shipping fees, into your sales prices or your profit margins
make sure you factor any other considerations or costs, like taxes, time value of money, your own time spent, space in your house, time doing all these calculations, time learning to grade.
don't forget to factor in what happens if your comics come back at a lower grade than you expect
 
And then decide if your potential profit is worth it using your own preferences and personal criteria.  Good luck.
 
Of course if you LOVE these specific comics for whatever reason, you may still want to grade, even if the math doesn't work out.  Most of us have some graded comics that aren't technically 'worth it' to grade, but it was worth it to us.

Right. Which is why I recommended buying them already slabbed since the OP is new to collecting and grading, and probably lacks basic grading skills let alone the ability to detect restoration.

Protects against unexpected "surprises" in grade, restoration and/or completeness.
Caveat if the OP got the books at a screaming low deal or is OO, but even then, see above protection.
 
Oh, and WTTB fellow Zonie!

Unless there’s been some new development I’m unaware of, Cap #103 isn’t a key by any stretch. And unless it's is an ultra-high grade copy, which you say it’s not, it probably doesn’t make sense to slab it. If you are not planning to sell the other two soon and depending on the condition, slabbing the others doesn’t make sense to me. If you want low grade books slabbed your best bet may be to buy them already graded.

As stated above pics would be very helpful to determine an approximate grade.
Also depends on what you plan to do with the books, sell, display, just keep in your collection, read again???
Just looking quickly at eBay sold listings...
Iron Fist 14 CGC VG+ 4.5, recently sold for $73.00 and $99.00 each.
Captain America 100 CGC FN- 5.5 sold for $218.00 and a FN 6.0 sold for $203.00
Captain America 103 CGC VF+ 8.5 sold for $62.00
https://comics.ha.com/tutorial/comics-grading.s?show=comicdefinitions
 

Define "not the best condition". You may want to post pictures of them on the "Please Grade My" board, and ask there.

It never hurts to put a note on the bag with your desired key comment. This will usually prompt one of the graders to at least think about entering it into the system (if it hasn't been entered already). Most of the graders are pretty enthusiastic comic fans, too...that's why they became graders in the first place...