11. An online marketplace system for notifying users of time limited offers for seller-financed transactions, the marketplace system comprising: at least one processing device; and at least one computer readable storage device storing instructions that, when executed by the at least one processing device, cause the at least one processing device to: generate and store trust profiles for buyer users and seller users, using the at least one processing device, the trust profiles configured to allow both the buyer users and the seller users to evaluate trustworthiness of each other prior to entering into seller-financed transactions, wherein the trust profiles include reputation data including: reputational factors, including: at least one rating of at least one of a user's prior transactions, from another user; historical data about the user's conformance to terms of the user's prior transactions; and information about a verification level of the user; and a trust score computed based on at least some of the reputational factors, including a number of the user's prior transactions; receive descriptions of a plurality of transaction offerings from a plurality of the seller users of the online marketplace system, using the at least one processing device, wherein the transaction offerings are available from the seller users over time for a plurality of payments; generate, using the at least one processing device, a user interface presenting a plurality of listings and the trust profiles for the buyer users and the seller users, each of the listings including one of the descriptions of the plurality of transactions offerings, wherein the plurality of listings are associated with transaction offerings across a plurality of different transaction offering categories; present at least some of the plurality of listings to the buyer users through the user interface, using the at least one processing device; and facilitate, using the at least one processing device and through the user interface, negotiation of binding contracts between the buyer users and the seller users for transfer of the transaction offerings from the seller users to the buyer users, wherein the binding contracts define payment terms, and wherein the payment terms include prices and seller-financing terms including at least two payments to be made by the buyer users over a period of time, comprising: receive an offer from a first user of the buyer users and the seller users for one of the transaction offerings, the offer including offer details and a time limit; generate an offer alert from the offer that includes the offer details, the time limit, and a customized link, which is selectable by a second user of the buyer users and the seller users to view the offer on the online marketplace system; format the offer alert according to a preferred offer communication method for the second user; transmit the formatted offer alert to the second user over a wireless communication network, wherein the formatted offer alert upon receipt instantaneously activates an application on a remote computing device to display the formatted offer alert and enable connection via the customized link to the online marketplace system over the Internet; upon connection of the remote computing device via the customized link, generating for display on the remote computing device to the second user: a listing for the one of the transaction offerings; the offer including the offer details; the trust profile for the first user; and an option to accept the offer; and receive an acceptance from the second user.
11. An online marketplace system for notifying users of time limited offers for seller-financed transactions, the marketplace system comprising: at least one processing device; and at least one computer readable storage device storing instructions that, when executed by the at least one processing device, cause the at least one processing device to: generate and store trust profiles for buyer users and seller users, using the at least one processing device, the trust profiles configured to allow both the buyer users and the seller users to evaluate trustworthiness of each other prior to entering into seller-financed transactions, wherein the trust profiles include reputation data including: reputational factors, including: at least one rating of at least one of a user's prior transactions, from another user; historical data about the user's conformance to terms of the user's prior transactions; and information about a verification level of the user; and a trust score computed based on at least some of the reputational factors, including a number of the user's prior transactions; receive descriptions of a plurality of transaction offerings from a plurality of the seller users of the online marketplace system, using the at least one processing device, wherein the transaction offerings are available from the seller users over time for a plurality of payments; generate, using the at least one processing device, a user interface presenting a plurality of listings and the trust profiles for the buyer users and the seller users, each of the listings including one of the descriptions of the plurality of transactions offerings, wherein the plurality of listings are associated with transaction offerings across a plurality of different transaction offering categories; present at least some of the plurality of listings to the buyer users through the user interface, using the at least one processing device; and facilitate, using the at least one processing device and through the user interface, negotiation of binding contracts between the buyer users and the seller users for transfer of the transaction offerings from the seller users to the buyer users, wherein the binding contracts define payment terms, and wherein the payment terms include prices and seller-financing terms including at least two payments to be made by the buyer users over a period of time, comprising: receive an offer from a first user of the buyer users and the seller users for one of the transaction offerings, the offer including offer details and a time limit; generate an offer alert from the offer that includes the offer details, the time limit, and a customized link, which is selectable by a second user of the buyer users and the seller users to view the offer on the online marketplace system; format the offer alert according to a preferred offer communication method for the second user; transmit the formatted offer alert to the second user over a wireless communication network, wherein the formatted offer alert upon receipt instantaneously activates an application on a remote computing device to display the formatted offer alert and enable connection via the customized link to the online marketplace system over the Internet; upon connection of the remote computing device via the customized link, generating for display on the remote computing device to the second user: a listing for the one of the transaction offerings; the offer including the offer details; the trust profile for the first user; and an option to accept the offer; and receive an acceptance from the second user. 13. The online marketplace system of claim 11 , wherein the at least one processing device is further caused to: notify the buyer users and the seller users that an agreement has been reached; confirm receipt of first payments from the buyer users according to the payment terms; monitor conformance of the seller users to the seller-financing terms; monitor conformance of the buyer users to the payment terms over the periods of time; and update reputation data within the trust profiles based at least in part on the conformance of the seller users and the buyer users.