A few questions I hope someone can answer.
The reason Factom works with a token (Factoid) is to prevent it from SPAM. With Factoids you can buy (EC) Entry Credits.
2. Are the costs of 1 entry equal to 1 EC?
2. yes
yes, but only in some circumstances.
Entries need 1 EC per partial KiB. If an entry is 4310 bytes in payload, it will require a minimum of 5 ECs. There is a maximum payload size of 10240 bytes, which would require 10 ECs.
The bytes that are counted are the payload. This includes the content, as well as the data in the extIDs. Also charged is the 2 byte over head for each extid describing its length.
https://github.com/FactomProject/FactomDocs/blob/master/factomDataStructureDetails.md#entryWhen creating a new chain, it takes a new entry to be the first one in the chain. Since creating a new chain adds overhead into the system, it requires more ECs to make a chain. It takes an extra 10 ECs on top of the quantity for the payload to make a new chain. Making a chain takes between 11 and 20 ECs.