(Mishnah): One may increase the rental price but not the sale price (if it not paid for straight away).

How is this? If he rented him a courtyard and told him, "If you pay me all of it now, it will cost 10 selah, but if you pay me each month, it will cost one selah per month (thereby costing 2 selah more in total)'', it is permitted.

If he sold him a field and told him, "If you pay me all of it now, it will cost you 1000 zuz. If it will be at the time of threshing, it will cost 1200 zuz per year'', it is prohibited.

If he sold him the field and the buyer gave part of the money and the seller told him to pay the rest whenever he wishes and he can then take it, it is prohibited.

If Reuven lent Shimon money and Shimon gave Reuven his field as security. If Reuven told him, "If you do not repay me within 3 years'', the field is mine''; the field becomes his.

This was done by Beisus ben Zonin with the permission of the Chachamim.

(Gemara) - Beraisa: One who sells a field and tells the buyer, "on condition that I will be its sharecropper'' or "on condition that I will be a partner'' or "on condition that its tithes are mine'' or "on condition that when you sell it, you will sell it to me - meaning that whenever I wish I can give its value and take it back'', all of these are permitted.

If Shimon owed Reuven money and he wrote him over his field, if the seller eats the fruits, it is permitted; if the buyer eats the fruits, it is prohibited.

R. Yehudah: Either way, it is permitted. (R. Yehudah rules that "tzad echad b'ribis mutar' - if there is way of paying back the loan without it being in the form of ribis, the loan may be taken.)

R. Yehudah adds: (From the Mishnah) This was done by Beisus ben Zonin with the permission of the Chachamim.

Chachamim: This is no proof - it was a case of the seller eating the fruits (so of course it was permitted)!

R. Yochanan/ R. Elazar/ R. Hoshiyah: R. Yehudah learned his opinion from the case of houses in a walled city, as the Beraisa teaches...

Beraisa: The year that was stated in the Torah concerning houses in a walled city (that the seller of such a house has one year to redeem it from the buyer. During that time, the buyer lives there and when the field is returned, the seller returns all of the money to the buyer, meaning that the buyer is 'consuming the fruits of the rental' during that time.)...it is like ribis (as in addition to the buyer being returned his money, he also received use of the house) but not actually ribis (as it was done as part of a sale rather than a loan).

Beraisa #2: This is a situation of actual ribis but the Torah nevertheless permitted it.

The first Beraisa is the opinion of R. Yehudah (who holds that tzad echad b'ribis) is permitted; the second Beraisa is the opinion of R. Meir (who holds that it is prohibited.)

R. Idi: When I came from the Diaspora, I saw a case come before R. Ami (where a borrower made a stipulation that if he did not return the debt on time, the lender could take the house. He actually did pay on time) and R. Ami ruled that it is like ribis (like the first Beraisa) and is permitted.

R. Chizkiyah: The Chachamim in fact said that this is actually ribis, but the Torah permitted it (in the case of the houses). However, it is specifically in this case that the Torah permitted it but in the case of a loan, it is not permitted (and he would need to return the rental money).

Despite this (statement of R. Chizkiyah), R. Ami did not retract his opinion and he held that the rent money need not be returned, since it is beneficial to the owner if a tenant occupies the house, because if any cracks develop, he will fill them in.